SABRE CATALYSTS CONTAINING FLUORINATED CARBON CHAINS FOR DELIVERY OF METAL-FREE MRI CONTRAST AGENTS

Abstract

Disclosed are perfluorinated SABRE catalysts comprising a d-block element and a perfluorinated ligand, wherein the perfluorinated ligand is of Formula (I): [L.sub.m-(NHC)(YZ).sub.q] or a salt thereof. Also disclosed is a method of preparing a hyperpolarized substrate comprising a spin nucleus or nuclei using the perfluorinated SABRE catalysts, and isolating the resulting hyperpolarized substrate for administration to an animal. Further disclosed is a method of imaging a tissue of an animal suspected of having a disease or condition.

Claims

1. A perfluorinated SABRE catalyst comprising a d-block element and a perfluorinated ligand, wherein the perfluorinated ligand is of Formula (I):
[L.sub.m-(NHC)(YZ).sub.q] Formula (I), or a salt thereof, and wherein each L is independently selected from hydrogen, adamantyl, a substituted or unsubstituted aromatic group, or a substituted or unsubstituted heteroaromatic group, NHC is a 4 to 7-membered N-heterocyclic carbenyl group where NHC is bound to the d-block element via a carbene, each Y is independently selected from a bond or a spacer group, each Z is a perfluorinated tag, m is an integer from 1 to 4, and q is an integer from 1 to 3.

2. The perfluorinated SABRE catalyst of claim 1, wherein NHC is a 5-membered N-heterocyclic carbenyl group.

3. (canceled)

4. The perfluorinated SABRE catalyst of claim 1, wherein NHC is a 4,5-disubstituted, a 1,3-disubstituted, or a 1,3,4,5-tetrasubstituted imidazole-based or imidazoline-based 5-membered N-heterocyclic carbenyl group.

5. The perfluorinated SABRE catalyst of claim 1, wherein NHC is a 4,5-disubstituted imidazolidinyl, a 1,3-disubstituted imidazolidinyl, a 1,3,4,5-tetrasubstituted imidazolidinyl, a 4,5-disubstituted 2,3-dihydro-imidazolyl, a 1,3-disubstituted 2,3-dihydro-imidazolyl, or a 1,3,4,5-tetrasubstituted 2,3-dihydro-imidazolyl.

6. The perfluorinated SABRE catalyst of claim 1, wherein the perfluorinated ligand is of Formula (Ia) or (Ib): ##STR00043## or a salt thereof, and wherein each L independently is hydrogen, adamantyl, a substituted or unsubstituted aromatic group, or a substituted or unsubstituted heteroaromatic group, each Y independently is a bond or a spacer group, each Z independently is a perfluorinated tag, is a single bond or a double bond, and represents the bond to the d-block element via the carbene.

7. The perfluorinated SABRE catalyst of claim 1, wherein the perfluorinated ligand is of Formula (Ic) or (Id): ##STR00044## or a salt thereof, and wherein each L independently is hydrogen, adamantyl, a substituted or unsubstituted aromatic group, or a substituted or unsubstituted heteroaromatic group, a is 4 to 20, b=2a+1 or b=a1, each n independently is an integer from 0 to 4, is a single bond or a double bond, and represents the bond to the d-block element via the carbene.

8. The perfluorinated SABRE catalyst of claim 1, wherein the perfluorinated ligand is of Formula (Ie) or (If): ##STR00045## or a salt thereof, and wherein each L independently is hydrogen, adamantyl, a substituted or unsubstituted aromatic group, or a substituted or unsubstituted heteroaromatic group, each Ar independently is a substituted or unsubstituted aromatic group, or a substituted or unsubstituted heteroaromatic group, each G independently is a bond, C.sub.1-6 alkyl, C.sub.1-6 alkenyl, or C.sub.1-6 heteroalkyl, a is 4 to 20, b=2a+1 or b=a1, is a single bond or a double bond, and represents the bond to the d-block element via the carbene.

9.-18. (canceled)

19. The perfluorinated SABRE catalyst of claim 1, wherein the perfluorinated ligand is ##STR00046## or a salt thereof, and wherein is a single bond or a double bond, and represents the bond to the d-block element via the carbene.

20.-23. (canceled)

24. A method of preparing the perfluorinated SABRE catalyst of claim 1, comprising reacting a perfluorinated compound with a base to form a carbene, and reacting the carbene with [(d-block element)(COD)Cl].sub.2, wherein COD stands for cyclooctadienyl.

25. (canceled)

26. A method of preparing a hyperpolarized substrate, the method comprising: (i) providing a perfluorinated SABRE catalyst according to claim 1; (ii) providing a co-ligand to interact with the perfluorinated SABRE catalyst to facilitate formation of an active perfluorinated SABRE catalyst; (iii) combining the active perfluorinated SABRE catalyst with parahydrogen and a substrate comprising a spin nucleus or nuclei in a solvent to obtain a reaction mixture; and (iv) hyperpolarizing the mixture obtained in (iii) by exposing the mixture to a magnetic field or by radiofrequency excitation to obtain a hyperpolarized active perfluorinated SABRE catalyst-substrate and/or a hyperpolarized substrate.

27.-32. (canceled)

33. The method of claim 26, wherein the co-ligand is dimethyl sulfoxide or phenyl trifluoromethyl sulfoxide.

34.-48. (canceled)

49. The method of claim 26, wherein the substrate is selected from 1-.sup.13C-ketoglutarate, 1-.sup.13C-5-.sup.12C-ketoglutarate, 1-.sup.13C-pyruvate, 1-.sup.13CN-acetyl cysteine, .sup.15N.sub.2-isoniazid (or pyridyl-4-carbo-bis-.sup.15N.sub.2-hydrazide), .sup.13C.sub.2, .sup.15N.sub.3-metronidazole, .sup.15N.sub.2-1-aminoisoquinoline (1-AIQ), deuterated versions thereof, and salts thereof.

50. The method of claim 26, wherein the substrate is of Formula (II): ##STR00047## wherein each R.sub.1 is independently selected from hydrogen, deuterium, a cation, C.sub.1-C.sub.6 alkyl, C.sub.3-C.sub.7cycloalkyl, (C.sub.3-C.sub.7 cycloalkyl) C.sub.1-C.sub.6 alkyl, (heterocycloalkyl) C.sub.1-C.sub.6 alkyl, (heteroaryl) C.sub.1-C.sub.6 alkyl, and (aryl) C.sub.1-C.sub.6 alkyl; and wherein Xa, Xb, Xc, and Xd are each independently hydrogen or deuterium, provided that at least one of Xa, Xb, Xc, and Xd is deuterium, or a pharmaceutically acceptable salt thereof.

51. A hyperpolarized substrate obtained from the method of claim 26, or a pharmaceutically acceptable salt thereof.

52. A pharmaceutical composition comprising a hyperpolarized substrate of claim 51, or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier.

53. A method of obtaining a magnetic resonance image of a tissue in a subject having or suspected to have a cancer or an adverse vascular condition comprising administering to the subject a hyperpolarized substrate according to claim 51 or a pharmaceutical composition comprising the hyperpolarized substrate and imaging the subject by magnetic resonance imaging.

54.-57. (canceled)

58. A perfluorinated compound of Formula (III): ##STR00048## wherein each Ar is independently selected from a substituted or unsubstituted aromatic group or a substituted or unsubstituted heteroaromatic group, each Ar.sub.f is independently selected from a perfluorinated substituted or unsubstituted aromatic group or a perfluorinated substituted or unsubstituted heteroaromatic group, each Y is independently selected from a bond or a spacer group, X is an anion, and is a single bond or a double bond.

59.-62. (canceled)

63. A method of preparing the perfluorinated compound according to claim 58, the method comprising: (i) reacting an alpha-bromo ketone comprising a perfluorinated substituted or unsubstituted aromatic group or a perfluorinated substituted or unsubstituted heteroaromatic group with an amidine comprising a substituted or unsubstituted aromatic group or a substituted or unsubstituted heteroaromatic group in the presence of a base to form an alpha-amino ketone, (ii) optionally reducing the alpha-amino ketone with a reducing agent to form an alpha-amino alcohol, and (iii) cyclizing the alpha-amino ketone or the alpha-amino alcohol to form the perfluorinated compound.

64. An olefin metathesis catalyst comprising a d-block element and a perfluorinated compound according to claim 58 as a ligand.

65. A method of polymerizing an olefin, the method comprising combining the olefin metathesis catalyst of claim 64 and the olefin in a reaction mixture.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0033] FIG. 1 illustrates a fluorous solid phase extraction (F-SPE) process wherein an organic fraction containing a hyperpolarized substrate is separated from the fluorous fraction on a fluorous silica gel with a fluorophobic solvent, or a fluorophobic pass, followed by recovering the fluorous fraction, which contains the perfluorinated SABRE catalyst with aqueous/organic solvents, or a fluorophilic pass, in accordance with an aspect of the invention.

[0034] FIG. 2 illustrates the substrate polarization process and its extraction from the SABRE catalyst from the fluorous silica gel illustrated in FIG. 1 by a fluorophilic pass, for example, using methanol or ethanol, in accordance with an aspect of the invention.

[0035] FIG. 3 illustrates a reverse F-SPE process wherein the fluorous fraction is separated from the aqueous/organic fraction on a standard silica gel with a fluorophilic solvent, or fluorophilic pass, in accordance with an aspect of the invention. The hyperpolarized substrate present in the organic fraction is recovered from the silica gel by extraction with a standard organic solvent, or by a fluorophobic pass.

[0036] FIG. 4 illustrates the partitioning of the perfluorinated SABRE catalyst and the hyperpolarized substrate between two immiscible phases (fluorous solvent fraction and water or another water immiscible solvent such as chlorinated solvents and water or other hydrophilic solvent(s)) in accordance with an aspect of the invention, which allows the principles of phase-transfer catalysis to be employed in conjunction with parahydrogen to produce high levels of hyperpolarization in the aqueous phase without catalyst contamination.

[0037] FIG. 5 illustrates the hyperpolarization of a fluorinated SABRE catalyst containing a metal and coordinated to a co-ligand and a substrate containing a half spin nucleus to form a hyperpolarized substrate that is free or substantially free of the perfluorinated SABRE catalyst, in accordance with an aspect of the invention.

[0038] FIG. 6 depicts, in the top curve, a single-scan HP .sup.13C spectrum obtained from the activated SABRE-SHEATH experiment of 30 mM sodium [1-.sup.13C]pyruvate, 42 mM p-trifluoromethyl phenyl sulfoxide (PTFSO), 7.8 mM IrFIMes shown in Example 5 in deuterated methanol. The spectrum was acquired immediately following manual sample transfer to a 1 T benchtop NMR after 55 seconds of 50% p-H.sub.2 bubbling at BT=0.7 T. The bottom curve shows a single-scan thermally polarized .sup.13C signal from 4 M sodium [1-.sup.13C] acetate using similar acquisition parameters. Enhancement is 1250 and polarization is about P(.sup.13C)0.1%.

[0039] FIG. 7 provides a graph showing the perfluorinated SABRE catalyst activation time, as described in Example 6.

[0040] FIG. 8 provides a schematic showing the formation of Complex 2, Complex 3a, Complex 3b, and pyruvate, as described in Example 6.

[0041] FIGS. 9A and 9B provide graphs showing the polarization (%) as a function of parahydrogen flow rate and pressure, respectively, as described in Example 7.

[0042] FIGS. 10A and 10B provide graphs showing the level of .sup.13C polarization transfer as a function of temperature and magnetic field, respectively, as described in Example 7.

[0043] FIGS. 11A and 11B provide graphs showing the polarization (%) as a function of perfluorinated SABRE catalyst concentration and DMSO concentration, respectively, as described in Example 7.

[0044] FIGS. 12A and 12B provide graphs showing the relaxation dynamics of [1-.sup.13C]-pyruvate, prepared by the method set forth in Example 7, where FIG. 12A shows the build up and relaxation at 0.4 T and FIG. 12B shows the relaxation at 1.81 T and the Earth's field.

[0045] FIG. 13 shows a comparison of a representative spectrum of .sup.13C-hyperpolarized [1-.sup.13C]-pyruvate with signal enhancement of 86500 fold, corresponding to P.sub.13C of 13.48%, as evidenced by the top spectrum of FIG. 13 as compared to the bottom spectrum of FIG. 13 showing a single-scan thermally polarized .sup.13C signal from 4 M sodium [1-.sup.13C] acetate using similar acquisition parameters, as described in Example 7.

[0046] FIG. 14 shows a variable temperature SABRE-SHEATH experiment using the saturated perfluorinated SABRE catalyst of Example 4, as described in Example 7.

[0047] FIG. 15 shows a comparison of a representative spectrum of .sup.13C-hyperpolarized [1-.sup.13C]-pyruvate after reconstitution in water with signal enhancement of 9000 fold, corresponding to P.sub.13C of 2.17%, as evidenced by the top spectrum of FIG. 15 as compared to the bottom spectrum of FIG. 15 showing a single-scan thermally polarized .sup.13C signal from 4 M sodium [1-.sup.13C] acetate using similar acquisition parameters, as described in Example 9.

[0048] FIG. 16 shows a comparison of a representative spectrum of .sup.13C-hyperpolarized [1-.sup.13C]-pyruvate with signal enhancement of 16900 fold, corresponding to P.sub.13C of 2.17%, as evidenced by the top spectrum of FIG. 16 as compared to the bottom spectrum of FIG. 16 showing a single-scan thermally polarized .sup.13C signal from 4 M sodium [1-.sup.13C] acetate using similar acquisition parameters, as described in Example 17.

[0049] FIG. 17 shows a comparison of a representative spectrum of .sup.13C-hyperpolarized [1-.sup.13C]-pyruvate with signal enhancement of 19000 fold, corresponding to P.sub.13C of 4.91%, as evidenced by the top spectrum of FIG. 17 as compared to the bottom spectrum of FIG. 17 showing a single-scan thermally polarized .sup.13C signal from 4 M sodium [1-.sup.13C] acetate using similar acquisition parameters, as described in Example 23.

[0050] FIG. 18 provides a graph showing the perfluorinated SABRE catalyst activation time in a fluorous mixture, as described in Example 24.

[0051] FIG. 19 provides a graph showing the polarization (%) as a function of parahydrogen flow rate in a fluorous mixture, as described in Example 25.

[0052] FIG. 20 provides a graph showing the level of .sup.13C polarization transfer as a function of magnetic field in a fluorous mixture, as described in Example 25.

[0053] FIGS. 21A and 21B provide graphs showing the relaxation dynamics of [1-.sup.13C]-pyruvate in a fluorous mixture, prepared by the method set forth in Example 25, where FIG. 21A shows the build up and relaxation at 0.4 T and FIG. 21B shows the relaxation at 1.81 T and the Earth's field.

[0054] FIG. 22 shows a comparison of a representative spectrum of .sup.13C-hyperpolarized [1-.sup.13C]-pyruvate in a fluorous mixture with signal enhancement of 38600 fold, corresponding to P.sub.13C of 6.02%, as evidenced by the top spectrum of FIG. 22 as compared to the bottom spectrum of FIG. 22 showing a single-scan thermally polarized .sup.13C signal from 4 M sodium [1-.sup.13C] acetate using similar acquisition parameters, as described in Example 25.

[0055] FIG. 23 shows a variable temperature SABRE-SHEATH experiment using the saturated perfluorinated SABRE catalyst of Example 4 in a fluorous mixture, as described in Example 25.

[0056] FIG. 24 shows a comparison of a representative spectrum of .sup.13C-hyperpolarized [1-.sup.13C]-pyruvate with signal enhancement of 10800 fold, corresponding to P.sub.13C of 1.68%, as evidenced by the top spectrum of FIG. 24 as compared to the bottom spectrum of FIG. 24 showing a single-scan thermally polarized .sup.13C signal from 4 M sodium [1-.sup.13C] acetate using similar acquisition parameters, as described in Example 26.

[0057] FIG. 25 shows a comparison of representative spectra of .sup.13C-hyperpolarized [1-.sup.13C]-pyruvate, prepared by a re-used catalyst, with signal enhancement of 3090 fold, corresponding to P.sub.13C of 0.48%, as evidenced by the bottom two spectra of FIG. 25 as compared to the top spectrum of FIG. 25 showing a single-scan thermally polarized .sup.13C signal from 4 M sodium [1-.sup.13C] acetate using similar acquisition parameters, as described in Example 26.

[0058] FIG. 26 shows an illustrative synthesis of 1,3-dimesityl-4,5-bis(2-(perfluorophenyl)ethyl)-4,5-dihydro-1H-imidazol-3-ium, triflate salt, as described in Example 27.

DETAILED DESCRIPTION OF THE INVENTION

[0059] The present invention provides a perfluorinated SABRE catalyst comprising a d-block element and a perfluorinated ligand, wherein the perfluorinated ligand is of Formula (I):

[L.sub.m-(NHC)(YZ).sub.q] Formula (I), [0060] or a salt thereof, and wherein [0061] each L is independently selected from hydrogen, adamantyl, a substituted or unsubstituted aromatic group, or a substituted or unsubstituted heteroaromatic group, [0062] NHC is a 4 to 7-membered N-heterocyclic carbenyl group where NHC is bound to the d-block element via a carbene, [0063] each Y is independently selected from a bond or a spacer group, [0064] each Z is a perfluorinated tag, [0065] m is an integer from 1 to 4 (e.g., 1, 2, 3, or 4), and [0066] q is an integer from 1 to 3 (e.g., 1, 2, or 3).

[0067] The perfluorinated SABRE catalyst comprises a d-block element such as, for example, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, La, Hf, Ta, W, Re, Os, Ir, Pt, Au, and/or Hg. In some embodiments, the d-block element is a transition metal such as, for example, Co, Rh, Ir, Ru, Pd, Pt, or Mt. In certain embodiments, the perfluorinated SABRE catalyst comprises an element of group 9 of the periodic table, i.e., Co, Rh, Ir, or Mt. In preferred embodiments, the perfluorinated SABRE catalyst comprises Ir or Co. For example, the perfluorinated SABRE catalyst can be prepared from [Ir(COD)(IMes)(Cl)].

[0068] The perfluorinated SABRE catalyst comprises a perfluorinated ligand of Formula (I):

[L.sub.m-(NHC)(YZ).sub.q Formula (I),

or a salt thereof, and wherein [0069] each L is independently selected from hydrogen, adamantyl, a substituted or unsubstituted aromatic group, or a substituted or unsubstituted heteroaromatic group, [0070] NHC is a 4 to 7-membered N-heterocyclic carbenyl group where NHC is bound to the d-block element via a carbene, [0071] each Y is independently selected from a bond or a spacer group, [0072] each Z is a perfluorinated tag, [0073] m is an integer from 1 to 4 (e.g., 1, 2, 3, or 4), and [0074] q is an integer from 1 to 3 (e.g., 1, 2, or 3).

[0075] In some aspects, NHC comprises an azolyl moiety, i.e., a five membered heterocyclic group having a nitrogen atom and at least one other hetero atom selected from nitrogen, sulfur, and oxygen. Thus, in some embodiments, NHC is a 5-membered N-heterocyclic carbenyl group. For example, the 5-membered N-heterocyclic carbenyl group can be imidazole-based, imidazoline-based, or thiazole-based. In other words, the 5-membered N-heterocyclic carbenyl group can be the resulting carbene formed from treatment of a perfluorinated ligand having an imidazole, an imidazoline, or a thiazole core.

[0076] In some embodiments, NHC is a 4,5-disubstituted, a 1,3-disubstituted, or a 1,3,4,5-tetrasubstituted imidazole-based or imidazoline-based 5-membered N-heterocyclic carbenyl group. For example, NHC can be a 4,5-disubstituted imidazolidinyl, a 1,3-disubstituted imidazolidinyl, a 1,3,4,5-tetrasubstituted imidazolidinyl, a 4,5-disubstituted 2,3-dihydro-imidazolyl, a 1,3-disubstituted 2,3-dihydro-imidazolyl, or a 1,3,4,5-tetrasubstituted 2,3-dihydro-imidazolyl. Examples of the imidazolylidinyl moiety include N,N-di-(2,4,6-trimethylphenyl)-imidazolylidinyl moiety, N,N-di-(2,6-diisopropylphenyl)-imidazolidinyl moiety, N,N-di-(2,6-dicyclohexyl)-imidazolidinyl moiety, N,N-di-(2,6-t-butyl)-imidazolidinyl moiety, and N,N-di-(1-adamantyl)-imidazolidinyl moiety.

[0077] In some embodiments, the perfluorinated ligand is of Formula (Ia) or (Ib):

##STR00002##

or a salt thereof, and wherein [0078] each L independently is hydrogen, adamantyl, a substituted or unsubstituted aromatic group, or a substituted or unsubstituted heteroaromatic group, [0079] each Y independently is a bond or a spacer group, [0080] each Z independently is a perfluorinated tag, [0081] is a single bond or a double bond, and [0082] represents the bond to the d-block element via the carbene.

[0083] In some embodiments, the perfluorinated ligand is of Formula (Ic) or (Id):

##STR00003##

[0084] or a salt thereof, and wherein [0085] each L independently is hydrogen, adamantyl, a substituted or unsubstituted aromatic group, or a substituted or unsubstituted heteroaromatic group, [0086] a is 4 to 20 (e.g., 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20), [0087] b=2a+1 or b=a1, [0088] each n independently is an integer from 0 to 4 (e.g., 0, 1, 2, 3, or 4), [0089] is a single bond or a double bond, and [0090] represents the bond to the d-block element via the carbene. In some embodiments of Formula (Ic) or (Id) a is 4 to 10 (e.g., 4, 5, 6, 7, 8, 9, or 10).

[0091] In some embodiments, the perfluorinated ligand is of Formula (Ie) or (If):

##STR00004##

or a salt thereof, and wherein [0092] each L independently is hydrogen, adamantyl, a substituted or unsubstituted aromatic group, or a substituted or unsubstituted heteroaromatic group, [0093] each Ar independently is a substituted or unsubstituted aromatic group, or a substituted or unsubstituted heteroaromatic group, [0094] each G independently is a bond, C.sub.1-6 alkyl, C.sub.1-6 alkenyl, or C.sub.1-6 heteroalkyl, [0095] a is 4 to 20 (e.g., 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20), [0096] b=2a+1 or b=a1, [0097] is a single bond or a double bond, and [0098] represents the bond to the d-block element via the carbene. In some embodiments of Formula (Ie) or (If), a is 4 to 10 (e.g., 4, 5, 6, 7, 8, 9, or 10).

[0099] In any of Formulae (I) and (Ia)-(If), each L is independently selected from hydrogen, adamantyl, a substituted or unsubstituted aromatic group, or a substituted or unsubstituted heteroaromatic group.

[0100] As used herein, substituted or unsubstituted aromatic refers to a substituted (e.g., C.sub.1-6 alkyl substituted) or unsubstituted aromatic ring having 5 to 60 ring carbon atoms, e.g., phenyl, naphthyl, phenanthryl, and anthracenyl. As used herein, substituted or unsubstituted heteroaromatic refers to a substituted (e.g., C.sub.1-6 alkyl substituted) or unsubstituted aromatic ring having from 1 to 2 heteroatoms chosen from N, O, and S, with remaining ring atoms being carbon, or a stable bicyclic or tricyclic system containing at least one 5- to 7-membered aromatic ring which contains from 1 to 3, or in some aspects, from 1 to 2, heteroatoms chosen from N, O, and S, with remaining ring atoms being carbon. Monocyclic heteroaryl groups typically have from 5 to 7 ring atoms, in some aspects, bicyclic heteroaryl groups are 9- to 10-membered heteroaryl groups, that is, groups containing 9 or 10 ring atoms in which one 5- to 7-member aromatic ring is fused to a second aromatic or non-aromatic ring. When the total number of S and O atoms in the heteroaryl group exceeds 1, these heteroatoms are not adjacent to one another. It is preferred that the total number of S and O atoms in the heteroaryl group is not more than 2. It is particularly preferred that the total number of S and O atoms in the aromatic heterocycle is not more than 1. Heteroaromatic groups include, but are not limited to, oxazolyl, piperazinyl, pyranyl, pyrazinyl, pyrazolopyrimidinyl, pyrazolyl, pyridizinyl, pyridyl, pyrimidinyl, pyrrolyl, quinolinyl, tetrazolyl, thiazolyl, thienylpyrazolyl, thiophenyl, triazolyl, henzofrijoxazolyl, benzofuranyl, benzothiazolyl, benzolhiophenyl, benzoxadiazolyl, dihydrobenzodioxynyl, furanyl, imidazolyl, indolyl, isothiazolyl, and isoxazolyl.

[0101] In some embodiments, each L independently is hydrogen, adamantyl, 2-methylphenyl, 3-methylphenyl, 4-methylphenyl, 2,4-dimethylphenyl, 2,5-dimethylphenyl, 2,6-dimethylphenyl, 3,5-dimethylphenyl, 2,4,6-trimethylphenyl, 2-ethylphenyl, 3-ethylphenyl, 4-ethylphenyl, 2,4-diethylphenyl, 2,5-diethylphenyl, 2,6-diethylphenyl, 3,5-diethylphenyl, 2,4,6-triethylphenyl, 2-npropylphenyl, 3-npropylphenyl, 4-npropylphenyl, 2,4-di-npropylphenyl, 2,5-di-npropylphenyl, 2,6-di-npropylphenyl, 3,5-di-npropylphenyl, 2,4,6-tri-npropylphenyl, 2-isopropylphenyl, 3-isopropylphenyl, 4-isopropylphenyl, 2,4-di-isopropylphenyl, 2,5-di-isopropylphenyl, 2,6-di-isopropylphenyl, 3,5-di-isopropylphenyl, 2,4,6-tri-isopropylphenyl, 2-isobutylphenyl, 3-isobutylphenyl, 4-isobutylphenyl, 2,4-di-isobutylphenyl, 2,5-di-isobutylphenyl, 2,6-di-isobutylphenyl, 3,5-di-isobutylphenyl, 2,4,6-tri-isobutylphenyl, 2-secbutylphenyl, 3-secbutylphenyl, 4-secbutylphenyl, 2,4-di-secbutylphenyl, 2,5-di-secbutylphenyl, 2,6-di-secbutylphenyl, 3,5-di-secbutylphenyl, 2,4,6-tri-secbutylphenyl, 2-tbutylphenyl, 3-/butylphenyl, 4-tbutylphenyl, 2,4-di-tbutylphenyl, 2,5-di-tbutylphenyl, 2,6-di-tbutylphenyl, 3,5-di-tbutylphenyl, 2,4,6-tri-butylphenyl, 2-cyclohexylphenyl, 3-cyclohexylphenyl, 4-cyclohexylphenyl, 2,4-di-cyclohexylphenyl, 2,5-di-cyclohexylphenyl, 2,6-di-cyclohexylphenyl, 3,5-di-cyclohexylphenyl, or 2,4,6-tri-cyclohexylphenyl. In certain embodiments of Formulae (I) and (Ia)-(If), each L independently is hydrogen or 2,4,6-trimethylphenyl.

[0102] In any of Formulae (I) and (Ia)-(If), each Y independently is a bond or a spacer group. For example, Y can be a bond, a substituted or unsubstituted C.sub.1-10 alkyl group, a substituted or unsubstituted C.sub.2-10 alkenyl group, a substituted or unsubstituted C.sub.2-10 alkynyl group, a substituted or unsubstituted C.sub.1-10 heteroalkyl group, a substituted or unsubstituted C.sub.3-6 cycloalkyl group, a substituted or unsubstituted C.sub.3-6 heterocycloalkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted alkaryl group, a substituted or unsubstituted arylalkyl group, or a linear or branched alkyleneoxy group (e.g., polyethylene oxide, polypropylene oxide, or a combination thereof).

[0103] In some embodiments, each Y independently is a bond, a substituted or unsubstituted C.sub.1-10 alkyl group, a substituted or unsubstituted C.sub.2-10 alkenyl group, a substituted or unsubstituted C.sub.2-10 alkynyl group, a substituted or unsubstituted C.sub.1-10 heteroalkyl group, a substituted or unsubstituted C.sub.3-6 cycloalkyl group, a substituted or unsubstituted C.sub.3-6 heterocycloalkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted alkaryl group, a substituted or unsubstituted arylalkyl group, or a linear or branched alkyleneoxy group. In certain embodiments, each Y independently is a bond, a substituted or unsubstituted C.sub.1-10 alkyl group, a substituted or unsubstituted C.sub.2-10 alkenyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted alkaryl group, or a substituted or unsubstituted arylalkyl group. In preferred embodiments, each Y independently is a bond, a substituted or unsubstituted C.sub.1-10 alkyl group, a substituted or unsubstituted C.sub.2-10 alkenyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted alkaryl group, or a substituted or unsubstituted arylalkyl group.

[0104] The perfluorinated ligand comprises a perfluorinated tag. For example, in any of Formulae (I) and (Ia)-(If), each Z is a perfluorinated tag. The perfluorinated tag can be any perfluorinated group such as, for example, a perfluorinated alkyl (e.g., linear or branched), aryl, alkyarl, or arylalkyl group containing up to 60 carbon atoms. In some embodiments, the perfluorinated tag is a perfluorinated C.sub.3-60 group comprising only carbon and fluorine atoms. In certain embodiments, the perfluorinated tag is a perfluorinated C.sub.3-40 group comprising only carbon and fluorine atoms. In other embodiments, the perfluorinated tag is a perfluorinated C.sub.3-20 group. For example, the perfluorinated tag can be selected from a C.sub.4F.sub.9 group, a C.sub.5F.sub.11 group, a C.sub.6F.sub.13 group, a C.sub.7F.sub.15 group, a C.sub.8F.sub.17 group, a C.sub.9F.sub.19 group, a C.sub.10F.sub.21 group, a C.sub.6F.sub.5 group, C.sub.4F.sub.7 group, a C.sub.5F.sub.9 group, a C.sub.6F.sub.11 group, a C.sub.7F.sub.13 group, a C.sub.8F.sub.15 group, a C.sub.9F.sub.17 group, and a C.sub.10F.sub.19 group, each of which can be a linear or branch alkyl, aryl, alkyarl, or arylalkyl group.

[0105] In an aspect, Z is a perfluoroalkyl chain, linear or branched, having a chain length of up to 60 or more carbon atoms, for example, the perfluoroalkyl chain has a chain length of 3-60, particularly, 3 to 40, more particularly 3 to 20, and even more particularly 3 to 10 or more, carbon atoms. For example, the perfluoroalkyl chain is selected from the group consisting of C.sub.4F.sub.9, C.sub.6F.sub.13, C.sub.7F.sub.15, C.sub.8F.sub.17, C.sub.9F.sub.19, and C.sub.10F.sub.21, preferably selected from the group consisting of C.sub.6F.sub.13, C.sub.8F.sub.17, and C.sub.10F.sub.21, each of which can be linear or branched and combinations thereof, wherein each of which can be linear or branched.

[0106] In an aspect, the perfluorinated ligand is of formula (Ig):

##STR00005##

or a salt thereof, and wherein [0107] a is 4 to 20 (e.g., 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20), [0108] b=2a+1 or b=a1, [0109] is a single bond or a double bond, and [0110] represents the bond to the d-block element via the carbene. In some embodiments of Formula (Ig), a is 4 to 10 (e.g., 4, 5, 6, 7, 8, 9, or 10).

[0111] In an aspect, the perfluorinated ligand is of formula (Ih):

##STR00006##

or a salt thereof, and wherein [0112] a is 4 to 20 (e.g., 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20), [0113] b=2a+1 or b=a1, [0114] is a single bond or a double bond, and [0115] represents the bond to the d-block element via the carbene. In some embodiments of Formula (Ig), a is 4 to 10 (e.g., 4, 5, 6, 7, 8, 9, or 10).

[0116] Exemplary perfluorinated ligands include:

##STR00007##

or a salt thereof, and wherein is a single bond or a double bond, and represents the bond to the d-block element via the carbene.

[0117] As used herein, the symbol represents a single bond or a double bond. In some embodiments, is a single bond. In other embodiments, is a double bond. In embodiments where is a single bond, the orientation of the two substituents stemming from can have any suitable stereochemistry, i.e., can be cis or trans. In preferred embodiments, when is a single bond, the stereochemistry of the substituents stemming from is trans.

[0118] As used herein, the symbol represents the bond to the d-block element via the carbene. In other words, represents the bond to the metal of the catalyst.

[0119] In some embodiments, the perfluorinated SABRE catalyst further comprises an additional ligand. For example, the perfluorinated SABRE catalyst may further comprise an additional ligand selected from phosphine ligands, carbene ligands, imidazole ligands, pincer chelating ligands, and compounds comprising a sulfoxide group. In certain embodiments, the perfluorinated SABRE catalyst comprises one or more phosphine ligands. Examples of phosphine ligands include, but are not limited to the following:

##STR00008##

[0120] In some embodiments, the perfluorinated SABRE catalyst comprises a pincer chelating ligand. Generally, when the perfluorinated SABRE catalyst comprises a phosphine ligand or a pincer chelating ligand, the perfluorinated SABRE catalyst is in pre-catalyst form. In some embodiments, the perfluorinated SABRE catalyst comprises a ligand that is a compound comprising a sulfoxide group. Examples of compounds comprising a sulfoxide group can be selected from the group consisting of dimethylsulfoxide (DMSO), phenyl trifluoromethyl sulfoxide, phenyl methyl sulfoxide, phenyl chloromethyl sulfoxide, diphenyl sulfoxide, dibenzoyl sulfoxide, and dibutyl sulfoxide. Generally, when the perfluorinated SABRE catalyst comprises a compound comprising a sulfoxide group, the perfluorinated SABRE catalyst is in active form. As used herein, the perfluorinated SABRE catalyst can refer to the active perfluorinated SABRE catalyst or the perfluorinated SABRE precatalyst.

[0121] The active perfluorinated SABRE catalyst can be prepared by any suitable method. Generally, the active perfluorinated SABRE catalyst is prepared by combining the perfluorinated SABRE precatalyst with a substrate, parahydrogen, and optionally a co-ligand in a solvent to form a mixture comprising an active perfluorinated SABRE catalyst. In some embodiments, the active perfluorinated SABRE catalyst is prepared by combining the perfluorinated SABRE precatalyst with a substrate, parahydrogen, and a co-ligand in a solvent to form a mixture comprising an active perfluorinated SABRE catalyst. The co-ligand, when included in the preparation of the active perfluorinated SABRE catalyst, can be combined with the perfluorinated SABRE precatalyst in any order and by any suitable means. For example, the co-ligand, when included in the preparation of the active SABRE catalyst, can be provided first to interact with the transfer precatalyst to facilitate formation of the active perfluorinated SABRE catalyst. Alternatively, the co-ligand, when included in the preparation of the active perfluorinated SABRE catalyst, can be added together with the substrate to facilitate formation of the active perfluorinated SABRE catalyst. In some embodiments, the co-ligand, the substrate, and parahydrogen are essentially combined with the perfluorinated SABRE precatalyst in the solvent at the same time to facilitate formation of the active perfluorinated SABRE catalyst. In other embodiments, the substrate is provided first to interact with the perfluorinated SABRE precatalyst to facilitate formation of the active SABRE catalyst. In some embodiments, the co-ligand and the substrate are combined with the perfluorinated SABRE precatalyst in the solvent, and the parahydrogen is added to (e.g., bubbled through) the resulting mixture. In other embodiments, the substrate is combined with the perfluorinated SABRE precatalyst in the solvent, and the parahydrogen is added to (e.g., bubbled through) the resulting mixture. In some embodiments, the active perfluorinated SABRE catalyst is prepared by combining the perfluorinated SABRE precatalyst with a co-ligand in addition to the substrate and parahydrogen.

[0122] In some embodiments, the active perfluorinated SABRE catalyst is of formula

[Ir(H).sub.2(F-IMes)(.sup.2-SUBSTRATE)(Co-ligand)] or

[Ir(H).sub.2(F-IMes)(.sup.1-SUBSTRATE)(Co-ligand).sub.2],

wherein SUBSTRATE is a target substrate to be hyperpolarized by the transfer of the pure singlet spin order of parahydrogen by the spin transfer catalyst, preferably a target substrate having enriched with an atom having spin nuclei, for example, .sup.1H, .sup.13C, .sup.15N, .sup.19F, .sup.31P and/or .sup.29Si. Without wishing to be bound by any particular theory, the co-ligand interacts with the spin transfer pre-catalyst to form the activated polarization transfer catalyst and enhances the polarization transfer to the target substrate. F-IMes refers to a perfluorinated form of N-heterocyclic carbenyl (NHC) ligand such as 1,3-Bis(2,4,6-trimethylphenyl)-1,3-dihydro-2H-imidazol-2-ylidene group.

[0123] In some embodiments, the perfluorinated SABRE catalyst (e.g., the perfluorinated SABRE precatalyst) can be prepared by a method comprising reacting a perfluorinated compound with a base to form a carbene, and reacting the carbene with [(d-block element)(COD)Cl].sub.2, wherein COD stands for cyclooctadienyl. In certain embodiments, the method comprises reacting a perfluorinated compound with a base to form a carbene, and reacting the carbene with [Ir(COD)Cl].sub.2. For example, a perfluorinated SABRE catalyst of formula:

##STR00009##

can be prepared by reacting a carbene of formula:

##STR00010##

with [Ir(COD)Cl].sub.2.

[0124] Exemplary perfluorinated SABRE catalysts (e.g., the perfluorinated SABRE precatalyst) include:

##STR00011##

or salts thereof.

[0125] The present invention further provides a method of preparing a hyperpolarized substrate, the method comprising: [0126] (i) providing a perfluorinated SABRE catalyst described herein; [0127] (ii) providing a co-ligand to interact with the perfluorinated SABRE catalyst to facilitate formation of an active perfluorinated SABRE catalyst; [0128] (iii) combining the active perfluorinated SABRE catalyst with parahydrogen and a substrate comprising a spin nucleus or nuclei in a solvent to obtain a reaction mixture; and [0129] (iv) hyperpolarizing the mixture obtained in (iii) by exposing the mixture to a magnetic field or by radiofrequency excitation to obtain a hyperpolarized active perfluorinated SABRE catalyst-substrate and/or a hyperpolarized substrate.

[0130] The methods of preparing a hyperpolarized substrate, described herein, comprise hyperpolarizing the mixture comprising the perfluorinated SABRE catalyst (e.g., the active perfluorinated SABRE catalyst) by exposing the mixture to a magnetic field or radiofrequency excitation to transfer the polarization from parahydrogen to the substrate to form the hyperpolarized substrate. Initially, the hyperpolarized substrate is complexed with the hyperpolarized perfluorinated SABRE catalyst; however, it will be understood by a person of ordinary skill in the art that the hyperpolarized substrate can be replaced by another substrate molecule such that the process can be repeated and the free hyperpolarized substrate bolus is produced.

[0131] The transfer of polarization from parahydrogen to the substrate to form the hyperpolarized substrate can occur under any suitable magnetic field or radiofrequency excitation. For example, the transfer of polarization from parahydrogen to the substrate can occur at a magnetic field below the magnetic field of earth. The suitable level of magnetic field or radiofrequency excitation necessary to transfer the polarization from parahydrogen to the substrate to form the hyperpolarized substrate will be readily apparent to a person of ordinary skill in the art.

[0132] In some embodiments, the method comprises replenishing the parahydrogen in the mixture during the step of hyperpolarizing the mixture comprising the perfluorinated SABRE catalyst (e.g., the active perfluorinated SABRE catalyst) by exposing the mixture to a magnetic field or radiofrequency excitation to transfer the polarization from parahydrogen to the substrate to form the hyperpolarized substrate. In other words, in some embodiments, the method comprises bubbling parahydrogen through the mixture comprising the perfluorinated SABRE catalyst (e.g., the active perfluorinated SABRE catalyst) during the step of hyperpolarizing the mixture comprising the perfluorinated SABRE catalyst (e.g., the active perfluorinated SABRE catalyst) by exposing the mixture to a magnetic field or radiofrequency excitation to transfer the polarization from parahydrogen to the substrate to form the hyperpolarized substrate.

[0133] The method of preparing a hyperpolarized substrate comprises providing a co-ligand to interact with the perfluorinated SABRE catalyst to facilitate formation of an active perfluorinated SABRE catalyst. The co-ligand can be any suitable compound containing one or more sulfoxide groups, thioester groups, phosphine groups, amine groups, CO groups, isonitrile groups, nitrogen-containing heterocyclic groups, or a combination thereof. In some embodiments, the co-ligand is a compound comprising a sulfoxide group. Examples of compounds comprising a sulfoxide group can be selected from the group consisting of DMSO, phenyl methyl sulfoxide, phenyl chloromethyl sulfoxide, diphenyl sulfoxide, dibenzoyl sulfoxide, phenyl trifluoromethyl sulfoxide, and dibutyl sulfoxide. In certain embodiments, the co-ligand is dimethyl sulfoxide or phenyl trifluoromethyl sulfoxide.

[0134] In embodiments of the method of preparing a hyperpolarized substrate, the magnetic field is an electro-magnetic field. For example, the strength of the electro-magnetic field can be in the range of 0-200 milliTeslas (mT). In some embodiments, the electro-magnetic field may be at least partially supplied by one or more permanent magnets in addition to or in lieu of the coil. In some embodiments, the electro-magnetic field may be an alternating magnetic field supplied at a frequency adapted to a particular nuclei. The alternating magnetic field can change directions (i.e., alternate between positive and negative relative to a positive direction). In some embodiments, the frequency can be a radio frequency, and preferably between 50 to 500 MHz, although other frequencies outside this range are contemplated as within the scope of the present disclosure.

[0135] The perfluorinated SABRE catalyst (e.g., active perfluorinated SABRE catalyst) is combined with parahydrogen and a substrate comprising a spin nucleus or nuclei in a solvent to obtain a reaction mixture. The solvent can be any suitable solvent capable of forming a heterogeneous or homogeneous mixture. In some embodiments, the solvent comprises water, methanol, ethanol, a fluorous solvent, or a mixture thereof. For example, the solvent can be ethanolic or methanolic, i.e., comprising at least ethanol or methanol in combination with water. In certain embodiments, the solvent comprises a fluorous solvent. In other embodiments, the solvent is deuterated such that a deuterated solvent can be prepared without (i.e., with limited) deuterium-hydrogen exchange.

[0136] The fluorous solvent can be any organic solvent comprising at least one compound having a fluorine atom. Without wishing to be bound by any particular theory, it is believed that the fluorous solvent increases the solubility of the perfluorinated SABRE catalyst. In some embodiments, the solvent (e.g., the fluorous solvent) is selected from a perfluorohexane/diethyl ether mixture, a methoxy nonafluorobutane and ethyl acetate mixture with a non-polar solvent, a perfluorohexane and ether mixture, a perfluorobutyl methyl ether and ethyl acetate mixture, an ether, a fluorocarbon derivative of THF FC 75, a decafluoromethoxy trifluoromethyl pentane, a hexafluoro propanol, a nonafluorobutyl methyl ether, a perfluoromethyl cyclohexane, a perfluoroalkane, a perfluorohexane, and a methoxy nonafluorobutane.

[0137] In some embodiments, the method of preparing a hyperpolarized substrate further comprises isolating the hyperpolarized substrate. The hyperpolarized substrate can be isolated by any suitable method. For example, the hyperpolarized substrate can be isolated by extraction, filtration, column chromatography, distillation, crystallization, or a combination thereof.

[0138] In some embodiments, the hyperpolarized substrate is isolated by treating the reaction mixture with a solid phase adsorbent to adsorb the perfluorinated SABRE catalyst, and recovering a liquid containing the hyperpolarized substrate, wherein the liquid is free (i.e., undetectable) or substantially free (e.g., less than 100 ppm, less than 50 ppm, less than 10 ppm, less than 5 ppm, or less than 1 ppm) of the perfluorinated SABRE catalyst. See, for example, FIG. 5. The solid phase adsorbent can be any suitable adsorbent capable of preferentially adsorbing the perfluorinated SABRE catalyst over the hyperpolarized substrate. For example the solid phase adsorbent can be a fluorous solid phase adsorbent, a reverse phase adsorbent (e.g., C18 adsorbents or the like), and polyethylene-based filters (e.g., ultrahigh molecular weight polyethylene). See, for example, FIGS. 1 and 2. In certain embodiments, the method of preparing a hyperpolarized substrate further comprises passing a fluorophobic solvent over the adsorbent and recovering an eluate containing the hyperpolarized substrate, wherein the eluate is free (i.e., undetectable) or substantially free (e.g., less than 100 ppm, less than 50 ppm, less than 10 ppm, less than 5 ppm, or less than 1 ppm) of the perfluorinated SABRE catalyst. The fluorophobic solvent can be any suitable solvent capable of preferentially washing the hyperpolarized substrate off of the solid phase adsorbent relative to the perfluorinated SABRE catalyst. For example, the fluorophobic solvent can comprise water and one or more of methanol, ethanol, acetonitrile, and dimethylformamide. Alternatively, or additionally, the method of preparing a hyperpolarized substrate can further comprise passing a fluorophilic solvent (e.g., a solvent comprising an organic solvent selected from methanol, ethanol, acetonitrile, THF, ethyl acetate, a chlorinated solvent (e.g., chlorinated alkanes such as methylene chloride, chloroform, and ethylene dichloride), and a combination thereof) over the adsorbent, for example, to recover the perfluorinated SABRE catalyst. Exemplary fluorophilic solvent systems include a perfluorohexane/diethyl ether mixture, a methoxy nonafluorobutane and ethyl acetate mixture, a perfluorohexane and diethyl ether mixture, a perfluorobutyl methyl ether and ethyl acetate mixture, or a diethyl ether.

[0139] In some embodiments, the hyperpolarized substrate is isolated by treating the reaction mixture with a solid phase adsorbent to adsorb the hyperpolarized substrate, and recovering a liquid containing the perfluorinated SABRE catalyst, wherein the liquid is free (i.e., undetectable) or substantially free (e.g., less than 100 ppm, less than 50 ppm, less than 10 ppm, less than 5 ppm, or less than 1 ppm) of the hyperpolarized substrate. The solid phase adsorbent can be any suitable adsorbent capable of preferentially adsorbing the hyperpolarized substrate over the perfluorinated SABRE catalyst. For example the solid phase adsorbent can be a normal phase adsorbent such as, for example silica, alumina, or the like. See, for example, FIG. 3. In certain embodiments, the method of preparing a hyperpolarized substrate further comprises passing a fluorophilic solvent over the adsorbent and recovering an eluate containing the perfluorinated SABRE catalyst, wherein the eluate is free (i.e., undetectable) or substantially free (e.g., less than 100 ppm, less than 50 ppm, less than 10 ppm, less than 5 ppm, or less than 1 ppm) of the hyperpolarized substrate. The fluorophilic solvent can be any suitable solvent capable of preferentially washing the perfluorinated SABRE catalyst off of the solid phase adsorbent relative to the hyperpolarized substrate. For example, the fluorophobic solvent can comprise a perfluorohexane/diethyl ether mixture, a methoxy nonafluorobutane and ethyl acetate mixture, a perfluorohexane and diethyl ether mixture, a perfluorobutyl methyl ether and ethyl acetate mixture, or a diethyl ether. Alternatively, or additionally, the method of preparing a hyperpolarized substrate can further comprise passing a fluorophobic solvent (e.g., a solvent comprising water, methanol, ethanol, acetonitrile, dimethylformamide, or a combination thereof) over the adsorbent, for example, to recover the hyperpolarized substrate.

[0140] In any of the embodiments disclosed herein, the perfluorinated SABRE catalyst and/or the hyperpolarized substrate can exist in a monophasic or a biphasic mixture. The monophasic or biphasic mixture can comprise any combination of solvents described herein. For example, the biphasic mixture can comprise a polar solvent (e.g., water, methanol, and ethanol) in combination with a non-polar solvent (e.g., an organic solvent or a fluorous solvent). In embodiments, where the perfluorinated SABRE catalyst and/or the hyperpolarized substrate exists in a biphasic solvent, the perfluorinated SABRE catalyst and/or the hyperpolarized substrate can be isolated by a liquid/liquid extraction. See, for example, FIG. 4. Thus, in some embodiments, the hyperpolarized substrate is isolated by a liquid/liquid extraction, for example, by partitioning the perfluorinated SABRE catalyst and the hyperpolarized substrate between a methanolic mixture and a fluorous solvent or partitioning the perfluorinated SABRE catalyst and the hyperpolarized substrate between a methanolic mixture and an organic solvent.

[0141] In some embodiments, the hyperpolarized substrate is isolated by precipitating the perfluorinated SABRE catalyst and filtering and removing the precipitated perfluorinated SABRE catalyst from the hyperpolarized substrate. Typically, the perfluorinated SABRE catalyst is precipitated by addition of solvents in which the perfluorinated SABRE catalyst is not soluble (e.g., hexane, pentane, water, ethanol, or the like). In certain embodiments, the perfluorinated SABRE catalyst is precipitated by the addition of water.

[0142] The perfluorinated SABRE catalyst and/or the hyperpolarized substrate can be dried or concentrated (e.g., under reduced pressure, using a desiccant, heating, or a combination thereof). Alternatively, or additionally, the perfluorinated SABRE catalyst and/or the hyperpolarized substrate can be diluted or reconstituted with a solvent (e.g., water) to provide a desired concentration. For example, the perfluorinated SABRE catalyst can be isolated and re-used as a hyperpolarization catalyst. Similarly, the hyperpolarized substrates can be dried or concentrated to remove organic solvents and reconstituted in water for administration to a subject.

[0143] The substrate can be any compound comprising a spin nucleus or nuclei. For example, the substrate can comprise .sup.1H, .sup.13C, .sup.15N, .sup.19F, .sup.31P, .sup.29Si, or a combination thereof. In some embodiments, the substrate further comprises .sup.2D. Thus, the methods described herein can be used to enhance the signal of .sup.1H, .sup.13C, .sup.15N, .sup.19F, .sup.31P and/or .sup.29Si response of a target substrate. Generally, the spin polarization transfer described herein is based on the SABRE effect; however the methods can be extended to parahydrogen-induced polarization (PHIP).

[0144] In some embodiments, the substrate is selected from ketoglutarate, pyruvate, N-acetyl cysteine, and salts or esters thereof. In certain embodiments, the substrate is selected from 1-.sup.13C-ketoglutarate, 1-.sup.13C-5-.sup.12C-ketoglutarate, 1-.sup.13C-pyruvate, 1-.sup.13CN-acetyl cysteine, .sup.15N.sub.2-isoniazid (or pyridyl-4-carbo-bis-.sup.15N.sub.2-hydrazide), .sup.13C.sub.2, .sup.15N.sub.3-metronidazole, .sup.15N.sub.2-1-aminoisoquinoline (1-AIQ), deuterated versions thereof, and salts thereof.

[0145] In some embodiments, the substrate is of Formula (II):

##STR00012## [0146] wherein each R.sub.1 is independently selected from hydrogen, deuterium, a cation, C.sub.1-C.sub.6 alkyl, C.sub.3-C.sub.7 cycloalkyl, (C.sub.3-C.sub.7 cycloalkyl) C.sub.1-C.sub.6 alkyl, (heterocycloalkyl) C.sub.1-C.sub.6 alkyl, (heteroaryl) C.sub.1-C.sub.6 alkyl, and (aryl) C.sub.1-C.sub.6 alkyl; and [0147] wherein Xa, Xb, Xc, and Xd are each independently hydrogen or deuterium, provided that at least one of Xa, Xb, Xc, and Xd is deuterium, [0148] or a pharmaceutically acceptable salt thereof.

[0149] Each R.sub.1 may be independently selected from hydrogen, deuterium, a cation, C.sub.1-C.sub.6 alkyl, C.sub.3-C.sub.7 cycloalkyl, (C.sub.3-C.sub.7 cycloalkyl) C.sub.1-C.sub.6 alkyl, (heterocycloalkyl) C.sub.1-C.sub.6 alkyl, (heteroaryl) C.sub.1-C.sub.6 alkyl, and (aryl) C.sub.1-C.sub.6 alkyl. In some embodiments, each R.sub.1 is independently selected from a C.sub.1-C.sub.6 alkyl, for example, each R.sub.1 can be methyl, ethyl, propyl (e.g., isopropyl or n-propyl), butyl (e.g., isobutyl, n-butyl, tert-butyl, or sec-butyl), pentyl, or hexyl. In some embodiments, each R.sub.1 is independently selected from hydrogen, deuterium, and a cation. In embodiments where R.sub.1 is a cation, it will be readily understood by a person of ordinary skill in the art that the compound of Formula (II) is a salt (e.g., a pharmaceutically acceptable salt) where the negative charge on oxygen is balanced by the cation. In certain embodiments, each R.sub.1 independently is a cation or C.sub.1-C.sub.6 alkyl.

[0150] The present invention further provides a hyperpolarized substrate, or a pharmaceutically acceptable salt, obtained from any of the methods described herein, or a pharmaceutical composition comprising a hyperpolarized substrate, or a pharmaceutically acceptable salt, and a pharmaceutically acceptable carrier. In other words, the present invention provides imaging medium (e.g., an aqueous imaging composition) with enhanced sensitivity on a water-soluble compound comprising a hyperpolarizable nucleus or hyperpolarizable nuclei, which imaging medium is particularly well suited for nuclear magnetic resonance (NMR) spectroscopy and/or magnetic resonance imaging (MRI).

[0151] The present invention further provides a method of obtaining a magnetic resonance image of a tissue in a subject having or suspected to have a cancer or an adverse vascular condition comprising administering to the subject a hyperpolarized substrate described herein, or a pharmaceutical composition thereof, and imaging the subject by magnetic resonance imaging. In an aspect, the subject has a cancer such as, for example, a cancer is selected from breast cancer, colon cancer, rectal cancer, bladder cancer, endometrial cancer, kidney cancer, lung cancer, melanoma, non-Hodgkin lymphoma, pancreatic cancer, prostate cancer, and thyroid cancer. In another aspect, the subject has an adverse vascular condition such as, for example, a vascular condition selected from myocardial infarction, stroke, and pulmonary disease (e.g., COPD, lung fibrosis, long-term COVID-19 symptom, and combinations thereof).

[0152] In some embodiments, the invention provides a method of diagnosing or monitoring a patient having or suspected to have a cancer, the method comprising administering a hyperpolarized substrate or a pharmaceutical composition as described above and diagnosing or monitoring the patient by hyperpolarized .sup.13C-MRI. For example, a hyperpolarized substrate can be used in the method of diagnosing or monitoring a patient having or suspected to have a cancer. In certain embodiments, the method or use comprises identifying a mutation or mutations responsible for the cancer. In certain embodiments, the method or use identifies an IDH1 mutation as being responsible for the cancer. In other words, the method or use can be used to identify whether the patient has a tumor, for example, an IDH1 mutation.

[0153] The present invention further provides a perfluorinated compound of Formula (III):

##STR00013##

wherein [0154] each Ar is independently selected from a substituted or unsubstituted aromatic group or a substituted or unsubstituted heteroaromatic group, [0155] each Ar.sub.f is independently selected from a perfluorinated substituted or unsubstituted aromatic group or a perfluorinated substituted or unsubstituted heteroaromatic group, [0156] each Y is independently selected from a bond or a spacer group, [0157] X is an anion, and [0158] is a single bond or a double bond.

[0159] All aspects of the perfluorinated compound of Formula (III) are as described with respect to any of Formulae (I) and (Ia)-(If). For example, Ar.sub.f is independently selected from a perfluorinated substituted or unsubstituted aromatic group or a perfluorinated substituted or unsubstituted heteroaromatic group, wherein substituted or unsubstituted aromatic group and substituted or unsubstituted heteroaromatic group are as described with respect to any of Formulae (I) and (Ia)-(If). In some embodiments of the perfluorinated compound of Formula (III), (i) each Ar is independently selected from a substituted or unsubstituted aromatic group, (ii) each Ar.sub.f is independently selected from a perfluorinated substituted or unsubstituted aromatic group, and/or (iii) each Y is independently selected from a spacer group selected from C.sub.1-5 alkyl and C.sub.1-5 heteroalkyl.

[0160] In certain embodiments, the perfluorinated compound is of Formula (IIIa):

##STR00014##

wherein [0161] each n independently is an integer from 0 to 4, [0162] X is an anion, and [0163] is a single bond or a double bond.

[0164] In Formulae (III) and (IIIa), X is an anion. X can be any suitable anion. For example, X can be a halide ion (e.g., fluoride chloride, bromide, or iodide) or a fluorate ion (e.g., tetrafluoroborate or hexafluorophosphate).

[0165] The perfluorinated compound of Formula (III) or (IIIa) can be prepared by any suitable means. For example, the perfluorinated compound can be prepared by a method comprising: [0166] (i) reacting an alpha-bromo ketone comprising a perfluorinated substituted or unsubstituted aromatic group or a perfluorinated substituted or unsubstituted heteroaromatic group with an amidine comprising a substituted or unsubstituted aromatic group or a substituted or unsubstituted heteroaromatic group in the presence of a base to form an alpha-amino ketone, [0167] (ii) optionally reducing the alpha-amino ketone with a reducing agent to form an alpha-amino alcohol, and [0168] (iii) cyclizing the alpha-amino ketone or the alpha-amino alcohol to form the perfluorinated compound.

[0169] The perfluorinated compound of Formula (III) or (IIIa) can be used in any suitable application. For example, the perfluorinated compound of Formula (III) or (IIIa) can be used for catalysis (e.g., polymerization catalysis or SABRE catalysis). Thus, in some embodiments, the invention provides a catalyst (e.g., an olefin metathesis catalyst or a SABRE catalyst) comprising a d-block element and a perfluorinated compound of Formula (III) or (IIIa) as a ligand, and a method of using the same. For example, the olefin metathesis catalyst, comprising a perfluorinated compound of Formula (III) or (IIIa), can be used in a method of polymerizing an olefin, the method comprising combining the olefin metathesis catalyst and an olefin in a reaction mixture. Similarly, the SABRE catalyst, comprising a perfluorinated compound of Formula (III) or (IIIa), can be used in a method of hyperpolarizing a substrate, as described herein.

Aspects of the Disclosure

[0170] Aspects, including embodiments, of the invention described herein may be beneficial alone or in combination, with one or more other aspects or embodiments. Without limiting the foregoing description, certain non-limiting aspects of the disclosure numbered 1-65 are provided below. As will be apparent to those of skill in the art upon reading this disclosure, each of the individually numbered aspects may be used or combined with any of the preceding or following individually numbered aspects. This is intended to provide support for all such combinations of aspects and is not limited to combinations of aspects explicitly provided below:

[0171] (1) In aspect (1) is provided a perfluorinated SABRE catalyst comprising a d-block element and a perfluorinated ligand, wherein the perfluorinated ligand is of Formula (I):

[L.sub.m-(NHC)(YZ).sub.q] Formula (I),

or a salt thereof, and wherein [0172] each L is independently selected from hydrogen, adamantyl, a substituted or unsubstituted aromatic group, or a substituted or unsubstituted heteroaromatic group, [0173] NHC is a 4 to 7-membered N-heterocyclic carbenyl group where NHC is bound to the d-block element via a carbene, [0174] each Y is independently selected from a bond or a spacer group, [0175] each Z is a perfluorinated tag, [0176] m is an integer from 1 to 4, and [0177] q is an integer from 1 to 3.

[0178] (2) In aspect (2) is provided the perfluorinated SABRE catalyst of aspect 1, wherein NHC is a 5-membered N-heterocyclic carbenyl group.

[0179] (3) In aspect (3) is provided the perfluorinated SABRE catalyst of aspect 2, wherein the 5-membered N-heterocyclic carbenyl group is imidazole-based, imidazoline-based, or thiazole-based.

[0180] (4) In aspect (4) is provided the perfluorinated SABRE catalyst of any one of aspects 1-3, wherein NHC is a 4,5-disubstituted, a 1,3-disubstituted, or a 1,3,4,5-tetrasubstituted imidazole-based or imidazoline-based 5-membered N-heterocyclic carbenyl group.

[0181] (5) In aspect (5) is provided the perfluorinated SABRE catalyst of any one of aspects 1-4, wherein NHC is a 4,5-disubstituted imidazolidinyl, a 1,3-disubstituted imidazolidinyl, a 1,3,4,5-tetrasubstituted imidazolidinyl, a 4,5-disubstituted 2,3-dihydro-imidazolyl, a 1,3-disubstituted 2,3-dihydro-imidazolyl, or a 1,3,4,5-tetrasubstituted 2,3-dihydro-imidazolyl.

[0182] (6) In aspect (6) is provided the perfluorinated SABRE catalyst of aspect 1, wherein the perfluorinated ligand is of Formula (Ia) or (Ib):

##STR00015##

or a salt thereof, and wherein [0183] each L independently is hydrogen, adamantyl, a substituted or unsubstituted aromatic group, or a substituted or unsubstituted heteroaromatic group, [0184] each Y independently is a bond or a spacer group, [0185] each Z independently is a perfluorinated tag, [0186] is a single bond or a double bond, and [0187] represents the bond to the d-block element via the carbene.

[0188] (7) In aspect (7) is provided the perfluorinated SABRE catalyst of aspect 1, wherein the perfluorinated ligand is of Formula (Ic) or (Id):

##STR00016## [0189] or a salt thereof, and wherein [0190] each L independently is hydrogen, adamantyl, a substituted or unsubstituted aromatic group, or a substituted or unsubstituted heteroaromatic group, [0191] a is 4 to 20, [0192] b=2a+1 or b=a1, [0193] each n independently is an integer from 0 to 4, [0194] is a single bond or a double bond, and [0195] represents the bond to the d-block element via the carbene.

[0196] (8) In aspect (8) is provided the perfluorinated SABRE catalyst of aspect 1, wherein the perfluorinated ligand is of Formula (Ie) or (If):

##STR00017## [0197] or a salt thereof, and wherein [0198] each L independently is hydrogen, adamantyl, a substituted or unsubstituted aromatic group, or a substituted or unsubstituted heteroaromatic group, [0199] each Ar independently is a substituted or unsubstituted aromatic group, or a substituted or unsubstituted heteroaromatic group, [0200] each G independently is a bond, C.sub.1-6 alkyl, C.sub.1-6 alkenyl, or C.sub.1-6 heteroalkyl, [0201] a is 4 to 20, [0202] b=2a+1 or b=a1, [0203] is a single bond or a double bond, and [0204] represents the bond to the d-block element via the carbene.

[0205] (9) In aspect (9) is provided the perfluorinated SABRE catalyst of aspect 7 or aspect 8, wherein a is 4 to 10.

[0206] (10) In aspect (10) is provided the perfluorinated SABRE catalyst of any one of aspects 1-9, where each L independently is hydrogen, adamantyl, 2-methylphenyl, 3-methylphenyl, 4-methylphenyl, 2,4-dimethylphenyl, 2,5-dimethylphenyl, 2,6-dimethylphenyl, 3,5-dimethylphenyl, 2,4,6-trimethylphenyl, 2-ethylphenyl, 3-ethylphenyl, 4-ethylphenyl, 2,4-diethylphenyl, 2,5-diethylphenyl, 2,6-diethylphenyl, 3,5-diethylphenyl, 2,4,6-triethylphenyl, 2-npropylphenyl, 3-npropylphenyl, 4-npropylphenyl, 2,4-di-npropylphenyl, 2,5-di-npropylphenyl, 2,6-di-npropylphenyl, 3,5-di-npropylphenyl, 2,4,6-tri-npropylphenyl, 2-isopropylphenyl, 3-isopropylphenyl, 4-isopropylphenyl, 2,4-di-isopropylphenyl, 2,5-di-isopropylphenyl, 2,6-di-isopropylphenyl, 3,5-di-isopropylphenyl, 2,4,6-tri-isopropylphenyl, 2-isobutylphenyl, 3-isobutylphenyl, 4-isobutylphenyl, 2,4-di-isobutylphenyl, 2,5-di-isobutylphenyl, 2,6-di-isobutylphenyl, 3,5-di-isobutylphenyl, 2,4,6-tri-isobutylphenyl, 2-secbutylphenyl, 3-secbutylphenyl, 4-secbutylphenyl, 2,4-di-secbutylphenyl, 2,5-di-secbutylphenyl, 2,6-di-secbutylphenyl, 3,5-di-secbutylphenyl, 2,4,6-tri-secbutylphenyl, 2-tbutylphenyl, 3-tbutylphenyl, 4-tbutylphenyl, 2,4-di-tbutylphenyl, 2,5-di-tbutylphenyl, 2,6-di-tbutylphenyl, 3,5-di-tbutylphenyl, 2,4,6-tri-tbutylphenyl, 2-cyclohexylphenyl, 3-cyclohexylphenyl, 4-cyclohexylphenyl, 2,4-di-cyclohexylphenyl, 2,5-di-cyclohexylphenyl, 2,6-di-cyclohexylphenyl, 3,5-di-cyclohexylphenyl, or 2,4,6-tri-cyclohexylphenyl.

[0207] (11) In aspect (11) is provided the perfluorinated SABRE catalyst of any one of aspects 1-10, where each L independently is hydrogen or 2,4,6-trimethylphenyl.

[0208] (12) In aspect (12) is provided the perfluorinated SABRE catalyst of any one of aspects 1-11, wherein each Y independently is a bond, a substituted or unsubstituted C.sub.1-10 alkyl group, a substituted or unsubstituted C.sub.2-10 alkenyl group, a substituted or unsubstituted C.sub.2-10 alkynyl group, a substituted or unsubstituted C.sub.1-10 heteroalkyl group, a substituted or unsubstituted C.sub.3-6 cycloalkyl group, a substituted or unsubstituted C.sub.3-6 heterocycloalkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted alkaryl group, a substituted or unsubstituted arylalkyl group, or a linear or branched alkyleneoxy group.

[0209] (13) In aspect (13) is provided the perfluorinated SABRE catalyst of any one of aspects 1-11, wherein each Y independently is a bond, a substituted or unsubstituted C.sub.1-10 alkyl group, a substituted or unsubstituted C.sub.2-10 alkenyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted alkaryl group, or a substituted or unsubstituted arylalkyl group.

[0210] (14) In aspect (14) is provided the perfluorinated SABRE catalyst of any one of aspects 1-11, wherein each Y independently is a bond, a substituted or unsubstituted C.sub.1-10 alkyl group, a substituted or unsubstituted C.sub.2-10 alkenyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted alkaryl group, or a substituted or unsubstituted arylalkyl group.

[0211] (15) In aspect (15) is provided the perfluorinated SABRE catalyst of any one of aspects 1-14, wherein the perfluorinated tag is a perfluorinated C.sub.3-60 group comprising only carbon and fluorine atoms.

[0212] (16) In aspect (16) is provided the perfluorinated SABRE catalyst of any one of aspects 1-14, wherein the perfluorinated tag is a perfluorinated C.sub.3-40 group comprising only carbon and fluorine atoms.

[0213] (17) In aspect (17) is provided the perfluorinated SABRE catalyst of any one of aspects 1-14, wherein the perfluorinated tag is a perfluorinated C.sub.3-20 group.

[0214] (18) In aspect (18) is provided the perfluorinated SABRE catalyst of any one of aspects 1-14, wherein the perfluorinated tag is selected from a C.sub.4F.sub.9 group, a C.sub.5F.sub.11 group, a C.sub.6F.sub.13 group, a C.sub.7F.sub.15 group, a C.sub.8F.sub.17 group, a C.sub.9F.sub.19 group, a C.sub.10F.sub.21 group, a C.sub.6F.sub.5 group, C.sub.4F.sub.7 group, a C.sub.5F.sub.9 group, a C.sub.6F.sub.11 group, a C.sub.7F.sub.13 group, a C.sub.8F.sub.15 group, a C.sub.9F.sub.17 group, and a C.sub.10F.sub.19 group.

[0215] (19) In aspect (19) is provided the perfluorinated SABRE catalyst of aspect 1, wherein the perfluorinated ligand is

##STR00018## [0216] or a salt thereof, and wherein [0217] is a single bond or a double bond, and [0218] represents the bond to the d-block element via the carbene.

[0219] (20) In aspect (20) is provided the perfluorinated SABRE catalyst of any one of aspects 1-19 wherein the d-block element is a transition metal.

[0220] (21) In aspect (21) is provided the perfluorinated SABRE catalyst of any one of aspects 1-20, wherein the d-block element is Co, Rh, Ir, Ru, Pd, Pt, or Mt.

[0221] (22) In aspect (22) is provided the perfluorinated SABRE catalyst of any one of aspects 1-21, wherein the SABRE catalyst further comprises an additional ligand.

[0222] (23) In aspect (23) is provided the perfluorinated SABRE catalyst of aspect 22, wherein the SABRE catalyst further comprises an additional ligand selected from phosphine ligands, carbene ligands, imidazole ligands, pincer chelating ligands, and compounds comprising a sulfoxide group.

[0223] (24) In aspect (24) is provided a method of preparing the perfluorinated SABRE catalyst of any one of aspects 1-23, comprising reacting a perfluorinated compound with a base to form a carbene, and reacting the carbene with [(d-block element)(COD)Cl].sub.2, wherein COD stands for cyclooctadienyl.

[0224] (25) In aspect (25) is provided the method of aspect 24, wherein the d-block element is Co, Rh, Ir, Ru, Pd, Pt, or Mt.

[0225] (26) In aspect (26) is provided a method of preparing a hyperpolarized substrate, the method comprising: [0226] (i) providing a perfluorinated SABRE catalyst according to any one of aspects 1-23; [0227] (ii) providing a co-ligand to interact with the perfluorinated SABRE catalyst to facilitate formation of an active perfluorinated SABRE catalyst; [0228] (iii) combining the active perfluorinated SABRE catalyst with parahydrogen and a substrate comprising a spin nucleus or nuclei in a solvent to obtain a reaction mixture; and [0229] (iv) hyperpolarizing the mixture obtained in (iii) by exposing the mixture to a magnetic field or by radiofrequency excitation to obtain a hyperpolarized active perfluorinated SABRE catalyst-substrate and/or a hyperpolarized substrate.

[0230] (27) In aspect (27) is provided the method of aspect 26, wherein the substrate comprises .sup.1H, .sup.13C, .sup.15N, .sup.19F, .sup.31P, .sup.29Si, or a combination thereof.

[0231] (28) In aspect (28) is provided the method of aspect 27, wherein the substrate further comprises .sup.2D.

[0232] (29) In aspect (29) is provided the method of aspect 27 or aspect 28, wherein the co-ligand is a compound containing one or more sulfoxide groups, thioester groups, phosphine groups, amine groups, CO groups, isonitrile groups, nitrogen-containing heterocyclic groups, or a combination thereof.

[0233] (30) In aspect (30) is provided the method of any one of aspects 26-29, wherein the solvent comprises water, methanol, ethanol, a fluorous solvent, or a mixture thereof.

[0234] (31) In aspect (31) is provided the method of any one of aspects 26-29, wherein the solvent comprises a solvent selected from a perfluorohexane/diethyl ether mixture, a methoxy nonafluorobutane and ethyl acetate mixture with a non-polar solvent, a perfluorohexane and ether mixture, a perfluorobutyl methyl ether and ethyl acetate mixture, an ether, a fluorocarbon derivative of THF FC 75, a decafluoromethoxy trifluoromethyl pentane, a hexafluoro propanol, a nonafluorobutyl methyl ether, a perfluoromethyl cyclohexane, a perfluoroalkane, a perfluorohexane, and a methoxy nonafluorobutane.

[0235] (32) In aspect (32) is provided the method of any one of aspects 26-31, wherein the solvent is deuterated.

[0236] (33) In aspect (33) is provided the method of any one of aspects 26-32, wherein the co-ligand is dimethyl sulfoxide or phenyl trifluoromethyl sulfoxide.

[0237] (34) In aspect (34) is provided the method of any one of aspects 26-33, further comprising (vi) isolating the hyperpolarized substrate.

[0238] (35) In aspect (35) is provided the method of aspect 34, wherein the hyperpolarized substrate is isolated by treating the reaction mixture with a solid phase adsorbent to adsorb the perfluorinated SABRE catalyst, and recovering a liquid containing the hyperpolarized substrate, wherein the liquid is free or substantially free of the perfluorinated SABRE catalyst.

[0239] (36) In aspect (36) is provided the method of aspect 35, further comprising passing a fluorophobic solvent over the adsorbent and recovering an eluate containing the hyperpolarized substrate, wherein the eluate is free or substantially free of the perfluorinated SABRE catalyst.

[0240] (37) In aspect (37) is provided the method of aspect 36, wherein the fluorophobic solvent comprises water and one or more of methanol, ethanol, acetonitrile, and dimethylformamide.

[0241] (38) In aspect (38) is provided the method of aspect 36 or aspect 37, further comprising passing a fluorophilic solvent over the adsorbent.

[0242] (39) In aspect (39) is provided the method of aspect 38, wherein the fluorophilic solvent comprises an organic solvent selected from methanol, ethanol, acetonitrile, THF, ethyl acetate, a chlorinated solvent, and a combination thereof.

[0243] (40) In aspect (40) is provided the method of aspect 34, wherein the hyperpolarized substrate is isolated by treating the reaction mixture with a solid phase adsorbent to adsorb the hyperpolarized substrate, and recovering a liquid containing the perfluorinated SABRE catalyst, wherein the liquid is free or substantially free of the hyperpolarized substrate.

[0244] (41) In aspect (41) is provided the method of aspect 40, further comprising passing a fluorophilic solvent over the adsorbent and recovering an eluate containing the perfluorinated SABRE catalyst, wherein the eluate is free or substantially free of the hyperpolarized substrate.

[0245] (42) In aspect (42) is provided the method of aspect 41, wherein the fluorophilic solvent comprises a perfluorohexane/diethyl ether mixture, a methoxy nonafluorobutane and ethyl acetate mixture, a perfluorohexane and diethyl ether mixture, a perfluorobutyl methyl ether and ethyl acetate mixture, or a diethyl ether.

[0246] (43) In aspect (43) is provided the method of aspect 34, wherein the hyperpolarized substrate is isolated by a liquid/liquid extraction.

[0247] (44) In aspect (44) is provided the method of aspect 43, wherein the liquid/liquid extraction comprises partitioning the perfluorinated SABRE catalyst and the hyperpolarized substrate between a methanolic mixture and a fluorous solvent.

[0248] (45) In aspect (45) is provided the method of aspect 43, wherein the liquid/liquid extraction comprises partitioning the perfluorinated SABRE catalyst and the hyperpolarized substrate between a methanolic mixture and an organic solvent.

[0249] (46) In aspect (46) is provided the method of aspect 34, wherein the hyperpolarized substrate is isolated by precipitating the perfluorinated SABRE catalyst and filtering and removing the precipitated perfluorinated SABRE catalyst from the hyperpolarized substrate.

[0250] (47) In aspect (47) is provided the method of aspect 46, wherein the perfluorinated SABRE catalyst is precipitated by the addition of water.

[0251] (48) In aspect (48) is provided the method of any one of aspects 26-47, wherein the substrate is selected from ketoglutarate, pyruvate, N-acetyl cysteine, and salts or esters thereof.

[0252] (49) In aspect (49) is provided the method of any one of aspects 26-48, wherein the substrate is selected from 1-.sup.13C-ketoglutarate, 1-.sup.13C-5-.sup.12C-ketoglutarate, 1-.sup.13C-pyruvate, 1-.sup.13CN-acetyl cysteine, .sup.15N.sub.2-isoniazid (or pyridyl-4-carbo-bis-.sup.15N.sub.2-hydrazide), .sup.13C.sub.2, .sup.15N.sub.3-metronidazole, .sup.15N.sub.2-1-aminoisoquinoline (1-AIQ), deuterated versions thereof, and salts thereof.

[0253] (50) In aspect (50) is provided the method of any one of aspects 26-48, wherein the substrate is of Formula (II):

##STR00019## [0254] wherein each R.sub.1 is independently selected from hydrogen, deuterium, a cation, C.sub.1-C.sub.6 alkyl, C.sub.3-C.sub.7 cycloalkyl, (C.sub.3-C.sub.7 cycloalkyl) C.sub.1-C.sub.6 alkyl, (heterocycloalkyl) C.sub.1-C.sub.6 alkyl, (heteroaryl) C.sub.1-C.sub.6 alkyl, and (aryl) C.sub.1-C.sub.6 alkyl; and [0255] wherein Xa, Xb, Xc, and Xd are each independently hydrogen or deuterium, provided that at least one of Xa, Xb, Xc, and Xd is deuterium, [0256] or a pharmaceutically acceptable salt thereof.

[0257] (51) In aspect (51) is provided a hyperpolarized substrate obtained from the method of any one of aspects 26-50, or a pharmaceutically acceptable salt thereof.

[0258] (52) In aspect (52) is provided a pharmaceutical composition comprising a hyperpolarized substrate of aspect 51, or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier.

[0259] (53) In aspect (53) is provided a method of obtaining a magnetic resonance image of a tissue in a subject having or suspected to have a cancer or an adverse vascular condition comprising administering to the subject a hyperpolarized substrate according to aspect 51 or a pharmaceutical composition according to aspect 52 and imaging the subject by magnetic resonance imaging.

[0260] (54) In aspect (54) is provided the method of aspect 53, wherein the subject has cancer.

[0261] (55) In aspect (55) is provided the method of aspect 54, wherein the cancer is selected from breast cancer, colon cancer, rectal cancer, bladder cancer, endometrial cancer, kidney cancer, lung cancer, melanoma, non-Hodgkin lymphoma, pancreatic cancer, prostate cancer, and thyroid cancer.

[0262] (56) In aspect (56) is provided the method of aspect 53, wherein the adverse vascular condition is selected from myocardial infarction, stroke, and pulmonary disease.

[0263] (57) In aspect (57) is provided the method of aspect 56, wherein the pulmonary disease is selected from COPD, lung fibrosis, long-term COVID-19 symptom, and a combination thereof.

[0264] (58) In aspect (58) is provided a perfluorinated compound of Formula (III):

##STR00020##

wherein [0265] each Ar is independently selected from a substituted or unsubstituted aromatic group or a substituted or unsubstituted heteroaromatic group, [0266] each Ar.sub.f is independently selected from a perfluorinated substituted or unsubstituted aromatic group or a perfluorinated substituted or unsubstituted heteroaromatic group, [0267] each Y is independently selected from a bond or a spacer group, [0268] X is an anion, and [0269] is a single bond or a double bond.

[0270] (59) In aspect (59) is provided the perfluorinated compound of aspect 58, wherein each Ar is independently selected from a substituted or unsubstituted aromatic group.

[0271] (60) In aspect (60) is provided the compound of aspect 58 or aspect 59, wherein each Ar.sub.f is independently selected from a perfluorinated substituted or unsubstituted aromatic group.

[0272] (61) In aspect (61) is provided the perfluorinated compound of any one of aspects 58-60, wherein each Y is independently selected from a spacer group selected from C.sub.1-5 alkyl and C.sub.1-5 heteroalkyl.

[0273] (62) In aspect (62) is provided the perfluorinated compound of aspect 58, wherein the perfluorinated compound is of Formula (IIIa):

##STR00021## [0274] wherein [0275] each n independently is an integer from 0 to 4, [0276] X is an anion, and [0277] is a single bond or a double bond.

[0278] (63) In aspect (63) is provided a method of preparing the perfluorinated compound according to any one of aspects 58-62, the method comprising: [0279] (i) reacting an alpha-bromo ketone comprising a perfluorinated substituted or unsubstituted aromatic group or a perfluorinated substituted or unsubstituted heteroaromatic group with an amidine comprising a substituted or unsubstituted aromatic group or a substituted or unsubstituted heteroaromatic group in the presence of a base to form an alpha-amino ketone, [0280] (ii) optionally reducing the alpha-amino ketone with a reducing agent to form an alpha-amino alcohol, and [0281] (iii) cyclizing the alpha-amino ketone or the alpha-amino alcohol to form the perfluorinated compound.

[0282] (64) In aspect (64) is provided an olefin metathesis catalyst comprising a d-block element and a perfluorinated compound according to any one of aspects 58-62 as a ligand.

[0283] (65) In aspect (65) is provided a method of polymerizing an olefin, the method comprising combining the olefin metathesis catalyst of aspect 64 and the olefin in a reaction mixture.

[0284] The following examples further illustrate the invention but, of course, should not be construed as in any way limiting its scope.

Example 1

[0285] This example illustrates a method of preparing 1H,1H,2H,2H-perfluorooctyl-N,N-bis(2,4,6-trimethylphenyl)-9,10-diamine:

##STR00022##

wherein x=6 and y=13.

[0286] A 1.7 M solution of tert-butyl lithium in pentane (5 mL, 9 mmol, 8 equiv.) was added to a solution of 1H,1H,2H,2H-perfluorooctyl iodide (2 g, 4 mmol, 4 equiv.) in dry Et.sub.2O (60 mL) at 78 C. After the mixture had been stirred for 20 min at 78 C., the solid N,N-dimesitylethanediimine (0.30 g, 1.03 mmol, 1 equiv.) was added portion wise. The reaction mixture was stirred for 4 h. The reaction was slowly warmed to 30 C. and quenched with a saturated solution of ammonium chloride (0.6 mL).

[0287] Water (20 mL) was added, the organic layer was separated, and the aqueous layer was extracted with diethyl ether (315 mL). The combined organic layers were dried over anhydrous MgSO.sub.4, and concentrated. The crude product was purified by flash column chromatography (4:1 hexane/dichloromethane (DCM)) to yield diamine, diimine, and threo-diamine (0.6 g, 60% yield, white solid). .sup.1H NMR (400 MHZ, CDCl.sub.3) 1.64-1.82 (m, 2H, CH.sub.2CHHCH(NHAr)), 2.00 (s, 12H, o-CH.sub.3), 2.07-2.27 (m, 4H, CHHCHHCH(NHAr)), 2.33 (s, 6H, p-CH.sub.3), 2.67-2.91 (m, 2H, CHHCH.sub.2CH(NHAr)), 2.95 (br s, 2H, NH), 3.23 (br d, .sup.3J.sub.H-H=10 Hz, 2H, CH), 6.82 (s, 4H, ArCH) ppm. .sup.19F NMR (282.23 MHZ, CDCl.sub.3) 83.8 (t, .sup.3J.sub.F-F=10 Hz, 6F, CF.sub.3), 114.4 (m, 4F, CF.sub.2CH.sub.2), 121.9 (m, 4F, CF.sub.2CF.sub.2CH.sub.2), 122.8 (m, 4F, CF.sub.3CF.sub.2CF.sub.2CF.sub.2), 123.4 (m, 4F, CF.sub.3CF.sub.2CF.sub.2), 126.1 (m, 4F, CF.sub.3CF.sub.2) ppm. .sup.13C NMR (400 MHz, CDCl.sub.3) 18.3 (o-CH.sub.3), 20.3 (p-CH.sub.3), 21.7 (m, CF.sub.2CH.sub.2CH.sub.2), 29.2 (t, .sup.2J.sub.F-C=22.2 Hz, CF.sub.2CH.sub.2), 57.1 (CH), 107-115 (m, 8 CF.sub.2), 117.4 (qt, .sup.1J.sub.F-C=288.3 Hz, .sup.2J.sub.F-C=33.3 Hz, CF.sub.3), 118.7 (tt, .sup.1J.sub.F-C=255.1 Hz, .sup.2J.sub.F-C=31.0 Hz, CF.sub.2CH.sub.2), 128.6 (ArC), 129.9 (ArCH), 131.4 (ArC),140.4 (ArC) ppm. MS (ESI), m/z (%): 990 [M+H].sup.+ (100).

Example 2

[0288] This example illustrates the synthesis of trans-4,5-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazolium tetrafluoroborate:

##STR00023##

[0289] A mixture of 1H,1H,2H,2H-Perfluorooctyl-N,N-bis(2,4,6-trimethylphenyl)-9,10-diamine (0.250 g, 0.25 mmol) from Example 1, ammonium tetrafluoroborate (10% molar excess) (0.030 g, 0.25 mmol), and triethyl orthoformate (0.5 mL) was heated to 125 C. and stirred for 15 h. After cooling to room temperature, the solution was evaporated and the solid was triturated with diethyl ether (63 mL). The residue was redissolved in acetone, filtered, and concentrated to yield to the dihydroimidazolium tetrafluoroborate. (0.2 g, 70% yield, yellowish solid). .sup.1H NMR (400 MHZ, acetone-d.sub.6) 2.15-2.70 (m, 8H, CF.sub.2CH.sub.2CH.sub.2), 2.34 (s, 6H, p-CH.sub.3), 2.51 (s, 6H, o-CH.sub.3), 2.94 (br s, 2H, NH), 5.16 (m, 2H, CH.sub.2CH.sub.2CH), 7.17 (s, 4H, ArCH), 9.06 (s, 1H, NCHN) ppm. .sup.19F NMR (400 MHZ, acetone-d.sub.6) 81.6 (t, .sup.4J.sub.F-F=10 Hz, 6F, CF.sub.3), 115.1 (m, 4F, CF.sub.2CF.sub.2CH.sub.2), 122.5 (m, 4F, CF.sub.2CF.sub.2CH.sub.2), 123.6 (m, 4F, CF.sub.3CF.sub.2CF.sub.2CF.sub.2), 124.5 (m, 4F, CF.sub.3CF.sub.2CF.sub.2), 126.9 (m, 4F, CF.sub.3CF.sub.2CF.sub.2), 150.9 (4F, BF.sub.4) ppm. .sup.13C NMR (400 MHZ, acetone-d.sub.6) 17.4 (o-CH.sub.3), 17.7 (o-CH.sub.3), 19.9 (p-CH.sub.3), 24.4 (m, CF.sub.2CH.sub.2CH.sub.2), 26.2 (t, .sup.2J.sub.F-C=22.2 Hz, CF.sub.2CH.sub.2), 67.9 (CH), 105-118 (m, 8 CF.sub.2), 118 (qt, .sup.1J.sub.F-C=288.3 Hz, .sup.2J.sub.F-C=33.3 Hz, CF.sub.3), 118.9 (tt, .sup.1J.sub.F-C=254 Hz, .sup.2J.sub.F-C=31.0 Hz, CF.sub.2CH.sub.2), 129.5 (ArC), 130.1 (ArCH), 130.5 (ArCH), 135.8 (ArC), 136 (ArC), 140.8 (ArC) ppm, 159.7 (NCN) ppm. MS (ESI) m/z (%): 999 [M+H].sup.+ (100).

Example 3

[0290] This example illustrates the synthesis of trans-4,5-Bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,3bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazolium chloride:

##STR00024##

[0291] Dihydroimidazolidium tetrafluoroborate salt (0.5 g, 0.46 mmol) was dissolved in MeOH (1.5 mL) and passed through a short column of ion exchange resin Amberlite 400. The column was washed with MeOH until no spot was visible via TLC under UV. The solvent was removed, and the resulting yellowish solid was dried with a vacuum pump to yield product (0.48 g, 99%). .sup.1H NMR (400 MHZ, acetone-d.sub.6) 2.15-2.70 (m, 8H, CF.sub.2CH.sub.2CH.sub.2), 2.34 (s, 6H, p-CH.sub.3), 2.51 (s, 6H, o-CH.sub.3), 2.94 (br s, 2H, NH), 5.16 (m, 2H, CH.sub.2CH.sub.2CH), 7.17 (s, 4H, ArCH), 9.06 (s, 1H, NCHN) ppm. .sup.19F NMR (400 MHZ, acetone-d.sub.6) 81.8 (t, .sup.4J.sub.F-F=10 Hz, 6F, CF.sub.3), 115.1 (m, 4F, CF.sub.2CF.sub.2CH.sub.2), 122.5 (m, 4F, CF.sub.2CF.sub.2CH.sub.2), 123.6 (m, 4F, CF.sub.3CF.sub.2CF.sub.2CF.sub.2), 124.5 (m, 4F, CF.sub.3CF.sub.2CF.sub.2), 127 (m, 4F, CF.sub.3CF.sub.2CF.sub.2) ppm. .sup.13C NMR (400 MHZ, acetone-d.sub.6) 17.4 (o-CH.sub.3), 17.7 (o-CH.sub.3), 19.9 (p-CH.sub.3), 24.4 (m, CF.sub.2CH.sub.2CH.sub.2), 26.2 (t, .sup.2J.sub.F-C=22.2 Hz, CF.sub.2CH.sub.2), 67.9 (CH), 105-118 (m, 8 CF.sub.2), 118 (qt, .sup.1J.sub.F-C=288.3 Hz, .sup.2J.sub.F-C=33.3 Hz, CF.sub.3), 118.9 (tt, .sup.1J.sub.F-C=254 Hz, .sup.2J.sub.F-C=31.0 Hz, CF.sub.2CH.sub.2), 129.5 (ArC), 130.1 (ArCH), 130.5 (ArCH), 135.8 (ArC), 136 (ArC),140.8 (ArC) ppm, 159.7 (NCN) ppm. MS (ESI) m/z (%): 999 [M+H].sup.+ (100).

Example 4

[0292] This example illustrates a method of synthesis of a fluorinated SABRE catalyst containing a transition metal in accordance with an aspect of the invention.

##STR00025##

[0293] Potassium tert-butoxide (112 mg, 1.00 mmol, 2.5 eq.) was added to a stirred solution of trans-4,5-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazolium chloride (320 mg, 0.88 mmol, 2.2 eq.) from Example 3 in tetrahydrofuran (10 mL) at room temperature in a glove box. The resulting suspension was stirred for 30 minutes. A solution of [Ir(COD)Cl].sub.2 (268 mg, 0.40 mmol, 1.0 eq.) was added and the resulting solution was stirred at room temperature overnight (Cowley et al., J. Am. Chem. Soc., 133, 6134-6137 (2011)). The solvent was removed under reduced pressure to give the crude product and dried overnight under vacuum. This sample was dissolved in hexane and added to a 60 mL filter packed with SiO.sub.2 gel in hexane. The crude solution was absorbed on the top of the silica gel, then hexane was added, to elute the compound, to give 104 mg (40% yield). .sup.1H NMR (400 MHZ, CDCl.sub.3) 1.04, 1.18, 1.49, 1.76, 2.13, 2.22, 2.25, 2.4, 2.48, 2.66, 2.94, 3.73, 4.01, 4.2, 6.84, 6.91 6.97 ppm. .sup.19F NMR (400 MHz, CDCl.sub.3) 81.08, 114.33, 122.05, 123.07, 124.02, 126.39 ppm. .sup.13C NMR (100 MHz, CDCl.sub.3) 18.7, 20.95, 21.07, 21.34, 26.45, 27.21, 29.83, 30.74, 31.42, 49.93, 55.12, 68.11, 68.47, 83.26, 86.69, 108.32, 111.0, 112.95, 115.85, 117.75, 118.69, 129.02, 129.3, 130.36, 130.55, 134.71, 134.8, 135.32, 136.33, 137.92, 138.28, 138.45, 138.5, 206.72 ppm. MS (ESI) m/z (%): 1299 [M+H].sup.+ (100).

Example 5

[0294] This example illustrates a method of hyperpolarizing a [1-.sup.13C]pyruvate in accordance with an aspect of the invention, as shown in Scheme 1.

[0295] Scheme 1. Hyperpolarization of [1-.sup.13C]pyruvate with phenyl trifluoromethyl sulfoxide as co-ligand.

##STR00026##

wherein co-ligand=phenyl trifluoromethyl sulfoxide.

[0296] In the reaction scheme above, hyperpolarization of [1-.sup.13C]pyruvate was performed using SABRE in SHield Enabled Alignment Transfer to Heteronuclei (SABRE-SHEATH) (Theis et al., J. Am. Chem. Soc., 137, 1404-1407 (2015) and Truong et al., J. Phys. Chem. C, 119, 8786-8797 (2015)) tailored for the .sup.13C nucleus (Barskiy et al., Chem Phys Chem, 18, 1493-1498 (2017)) using the co-ligand approach developed by Duckett and co-workers (Iali et al., Angew. ChemieInt. Ed., 58, 10271-10275 (2019)). Sodium [1-.sup.13C]-pyruvate and deuterated methanol-d.sub.4 solvent were purchased from Sigma-Aldrich and used without any further purification. The [IrCl(COD)(F-IMes)] SABRE catalyst used for this Example was prepared according to Example 4. The active catalyst used herein was prepared with a fixed ratio of substrate to Ir(F-IMes) SABRE catalyst of Example 4, and phenyl trifluoromethyl sulfoxide (PTFSO) in 0.6 mL of methanol-d.sub.4 in a 5 mm NMR tube.

[0297] Parahydrogen was generated using a Gas-Delivery Manifold. Ultra-high-purity hydrogen gas (Airgas) was fed into a ParaHydrogen flow cryostat (Xeus technology LTD) and enriched to about 50% parahydrogen in the presence of a spin-exchange catalyst (Fe.sub.2O.sub.3) at liquid nitrogen temperature (77K). The p-H.sub.2 flow was directed via PTFE tubing to a mass flow controller (MFC, Sierra Instruments SmartTrak 100 series) set at 90 scc/m and directed to a conventional 5 mm NMR tube (Norell) to allow bubbling through the sample. The entire pH2 line was pressurized to 100 psi.

[0298] The magnetic shield condition was as follows. Magnetic fields near or below 1 T were achieved with an apparatus consisting of a solenoid coil placed inside a mu-metal shield (Magnetic Shield Corporation, model No. ZG-206). The shield was degaussed using internal homebuilt coils driven by a Variac when necessary. The solenoid had a 41 mm diameter (40 mm core, 20 cm long windings with 220 turns AWG20 (0.9 mm) Cu wire and with 220 resistor in series. The solenoid coil was driven by commercial 1.5V batteries with a variable-resistance decade box in series to provide finer control of the internal magnetic field inside the shield. Typical values of the field within the shield were between 1.2 T, with SABRE SHEATH experiments typically between 0.7 T and +0.8 T in the sample region. The values were monitored between SABRE experiments using a Lakeshore Cryotronics Gaussmeter (Model No. 475 DSP with HMMA-2512-VR Hall Probe).

[0299] MR experiments were performed using a 1 T Magritek Spinsolve benchtop NMR spectrometer. All .sup.13C NMR spectra were taken with 1H decoupling turned off throughout the duration of the experiment. Time required to manually transfer the sample from the shield region to the magnet for low-field NMR acquisition was usually <5 s.

[0300] The efficient hyperpolarization transfer from nascent p-H.sub.2-derived hydrides to the .sup.13C nuclear spin of [1-.sup.13C]pyruvate was attained by performing SABRE in sub-microtesla magnetic fields using SABRE in SHield Enables Alignment Transfer to Heteronuclei (SABRE-SHEATH) using a solution mixture of [IrCl(H).sub.2(PTFSO).sub.2(F-IMes)], [1-.sup.13C]pyruvate) and p-H.sub.2 in deuterated methanol. FIG. 6 depicts, in the top curve, a single-scan HP .sup.13C spectrum obtained for the hyperpolarized probe. The bottom curve shows a single-scan thermally polarized .sup.13C signal from 4 M sodium [1-.sup.13C] acetate using similar acquisition parameters. Enhancement is 9000 and polarization is about P(.sup.13C)1%.

[0301] All experiments were performed with the solution containing fluorinated catalyst, co-ligand (phenyl trifluoromethyl sulfoxide) and [1-.sup.13C]Pyruvate in 0.6 mL CD.sub.3OD. The ratio and concentration can be further adjusted to attain better enhancement and polarization. The results were obtained for 8 mM fluorinated catalyst, 16 mM phenyl trifluoromethyl sulfoxide (PTFSO) and 30 mM [1-.sup.13C]Pyruvate in 0.6 mL CD.sub.3OD. The experiments were performed at room temperature, 100 scc/m p-H.sub.2 flow rate and 96 PSI p-H.sub.2 overpressure. The parahydrogen used in this example came from a low-cost 50% p-H.sub.2 generator. Each experiment, the p-H.sub.2 bubbling was applied for 1 min, the sample was quickly transferred to the 1 T NMR spectrometer for detection and the sample was then returned to the mu-metal shield to continue p-H.sub.2 bubbling for the next experiment. The .sup.13C signal enhancement was computed by comparing HP signal area-undercurve (AUC) to external .sup.13C signal thermal signal reference (4M sodium [1-.sup.13C]acetate) using Eq. 1:

[00001]$\begin{array}{cc}{(}^{13}C)=\frac{S_{HP}}{S_{REF}}.Math.\frac{C_{REF}}{C_{HP}}.Math.\frac{A_{REF}}{A_{HP}},& \left(1\right)\end{array}$

where S.sub.HP and S.sub.REF are .sup.13C signals from HP [1-.sup.13C] pyruvate and thermal signal reference [1-.sup.13C]acetate, C.sub.REF and C.sub.HP are concentrations of thermal signal reference [1-.sup.13C]acetate (4 M) and of HP [1-.sup.13C]pyruvate, respectively, and A.sub.REF and A.sub.HP are effective cross-sections of the NMR tubes for the thermal signal reference [1-.sup.13C]acetate and HP [1-.sup.13C]pyruvate samples.

Example 6

[0302] This example illustrates a method of hyperpolarizing a [1-.sup.13C]pyruvate in accordance with an aspect of the invention, as shown in Scheme 2.

Scheme 2. Hyperpolarization of [1-.sup.13C]Pyruvate Using the Perfluorinated SABRE Catalyst of Example 4 with Dimethyl Sulfoxide as Co-Ligand

##STR00027##

[0303] In the reaction scheme above, hyperpolarization of [1-.sup.13C]pyruvate was performed using SABRE in SHield Enables Alignment Transfer to Heteronuclei (SABRE-SHEATH) (Theis et al., J. Am. Chem. Soc., 137, 1404-1407 (2015) and Truong et al., J. Phys. Chem. C, 119, 8786-8797 (2015)) tailored for the .sup.13C nucleus (Barskiy et al., Chem Phys Chem, 18, 1493-1498 (2017)) using the co-ligand approach developed by Duckett and co-workers (Iali et al., Angew. ChemieInt. Ed., 58, 10271-10275 (2019)). Sodium [1-.sup.13C]-pyruvate and deuterated methanol-d.sub.4 solvent were purchased from Sigma-Aldrich and used without any further purification. The [IrCl(COD)(F-IMes)] SABRE catalyst used for this Example was prepared according to Example 4. The active catalyst used herein was prepared with a fixed ratio of substrate [1-.sup.13C]pyruvate, Ir(F-IMes) SABRE catalyst of Example 4, and co-ligand dimethyl sulfoxide (DMSO), in 0.6 mL of methanol-d.sub.4 in a 5 mm NMR tube.

[0304] Parahydrogen enriched to about 70 to 95% was used and directed via PTFE tubing to a mass flow controller (MFC, Sierra Instruments SmartTrak 100 series) set between 50 to 120 scc/m into a medium wall 5 mm NMR tube (Norell) to allow bubbling through the sample. The entire pH2 line was pressurized values between 50 and 110 psi.

[0305] The polarization transfer magnetic field was established as follows. Magnetic fields near or below 1 T were achieved with an apparatus consisting of a solenoid coil placed inside a three-layered mu-metal shield (6 in. ID & 15 in. in length, part number ZG-206, Magnetic Shield Corp., Bensenville, IL). The magnetic field was created using a custom-built solenoid coil and a triple independent channel DC power supply (KEITHLEY 2231A-30-3). The solenoid had a 41 mm diameter (40 mm core, 20 cm long windings with 220 turns AWG20 (0.9 mm) Cu wire and with 220 resistor in series. The solenoid coil was driven with a variable-resistance decade box in series to provide finer control of the internal magnetic field inside the shield. Typical values of the field within the shield were between 1.2 T, with SABRE SHEATH experiments typically between 0.7 T and +0.8 T in the sample region.

[0306] MR experiments were performed using an 80 MHz Magritek Spinsolve benchtop

[0307] NMR spectrometer. The following acquisition parameters were used: [0308] spectra width (SW)=5 kHz; [0309] dwell time (DT)=150 s; [0310] number of scans (ns)=1, [0311] receiver gain=16; [0312] excitation pulse angle (a)=90; [0313] .sup.13C resonance frequency=20.25232790 MHz.

[0314] All .sup.13C NMR spectra were taken with 1H decoupling turned off throughout the duration of the experiment. Time required to manually transfer the sample from the shield region to the magnet for low-field NMR acquisition was usually <5 s.

[0315] The hyperpolarization transfer from p-H.sub.2-derived iridium hydrides to the .sup.13C nuclear spin of [1-.sup.13C]pyruvate was attained by performing SABRE in sub-microtesla magnetic fields using SABRE in SHield Enables Alignment Transfer to Heteronuclei (SABRE-SHEATH) using a solution mixture of [IrCl(H).sub.2(DMSO).sub.2(F-IMes)], [1-.sup.13C]pyruvate, co-ligand (dimethyl sulfoxide) and p-H.sub.2 in 0.5 mL deuterated or non-deuterated methanol.

[0316] The .sup.13C signal enhancement was computed by comparing HP signal area-undercurve (AUC) to external .sup.13C signal thermal signal reference (4M sodium [1-.sup.13C]acetate) using Eq.:

[00002]$\begin{array}{cc}{(}^{13}C)=\frac{S_{HP}}{S_{REF}}.Math.\frac{C_{REF}}{C_{HP}}.Math.\frac{A_{REF}}{A_{HP}},& \left(1\right)\end{array}$

where S.sub.HP and S.sub.REF are .sup.13C signals from HP [1-.sup.13C]pyruvate and thermal signal reference [1-.sup.13C]acetate, C.sub.REF and C.sub.HP are concentrations of thermal signal reference [1-.sup.13C]acetate (4 M) and of HP [1-.sup.13C]pyruvate, respectively, and A.sub.REF and A.sub.HP are effective cross-sections of the NMR tubes for the thermal signal reference [1-.sup.13C]acetate and HP [1-.sup.13C]pyruvate samples. The percentage of .sup.13C polarization (% P.sup.13.sub.C) was computed by multiplying the signal enhancement (.sup..sub.C) by thermal .sup.13C nuclear spin polarization at 1.81 T (1.5681*10.sup.4%) in accordance with Equation S2: (% P.sup.13.sub.C), =.sup.13.sub.C*1.56181*10.sup.6*100.

[0317] The fluorinated SABRE catalyst activation took less than 15 minutes, with the .sup.13C polarization percentage shown in FIG. 7, and is performed by bubbling 95% p-H.sub.2 at a flow rate of 90 standard cubic centimeters per minute (scc/m) at 8 atm p-H.sub.2 partial pressure, which leads to the formation of Complex 2, Complex 3a, Complex 3b, and pyruvate, as depicted in FIG. 8, in accord with the notation introduced by Duckett and co-workers (Iali et al., Angew. ChemieInt. Ed., 58, 10271-10275 (2019)). Without wishing to be bound by any particular theory, it is believed that Complex 3B is the primary SABRE-active species.

Example 7

[0318] This example demonstrates the effects on hyperpolarization of [1-.sup.13C]pyruvate, exhibited by changes in parahydrogen pressure and flow rate, as well as the effect of magnetic transfer field, temperature, and concentration of the fluorinated catalyst and DMSO. In addition, the relaxation dynamics of the [1-.sup.13C]pyruvate were also studied.

[0319] Hyperpolarization of [1-.sup.13C]pyruvate was repeated using SABRE in SHield Enables Alignment Transfer to Heteronuclei (SABRE-SHEATH), as described in Example 6 above, and the effects of parahydrogen pressure and flow rate, as well as the effect of magnetic transfer field, temperature, and concentration of the fluorinated catalyst and DMSO, were studied.

[0320] p-H.sub.2 parameters such as the pressure and flow rate were evaluated and the polarization percentage results are set forth in FIGS. 9A and 9B. The NMR samples contained in 30 mM sodium [1-.sup.13C]pyruvate, 2.6 mM fluorinated SABRE catalyst, and 40 mM dimethyl sulfoxide (DMSO), the mixing field was at 0.4 T and temperature at 0 C. As is apparent from the results set forth in FIGS. 9A and 9B, as the parahydrogen flow rate and pressure increased, the polarization percentage also increased.

[0321] The temperature and magnetic field in the micro Tesla regime were evaluated and the .sup.13C polarization level and polarization transfer magnetic field at 0 C. are set forth in FIGS. 10A and 10B, respectively. The NMR samples contained in 30 mM sodium [1-.sup.13C]pyruvate, 2.6 mM fluorinated SABRE catalyst, and 40 mM dimethyl sulfoxide (DMSO), p-H.sub.2 flow and pressure 70 scc/m and 100 PSI. As is apparent from the results set forth in FIGS. 10A and 10B, the best polarization transfer occurs at temperatures between 20 C. and 5 C. and a mixing field between 0.3 T and 0.5 T. The optimum temperature is 7.24 C. and the optimum mixing field is 0.4 T.

[0322] The perfluorinated SABRE catalyst and DMSO concentrations were evaluated at a temperature of 0 C., a magnetic transfer field of 0.4 T, a p-H.sub.2 flow of 90 scc/m, and a p-H.sub.2 pressure of 110 PSI, and the polarization percentages are set forth in FIGS. 11A and 11B. As is apparent from the results set forth in FIG. 11A, the polarization percentage increases as the perfluorinated SABRE catalyst concentration increases. However, the polarization percentage remains relatively consistent at concentrations above 20 mM.

[0323] As is apparent from the results set forth in FIGS. 12A and 12B, the relaxation dynamics of [1-.sup.13C]-pyruvate show that the total P.sub.13C (bound+free) build-up time (T.sub.b=6.63.0 s) is substantially shorter than the corresponding T.sub.1 value of 16.10.9 s, which allows to reach P.sub.13C levels up to 13.48%. In addition, relaxation dynamics at earth field and 1.8 T are about the same as a non-fluorinated SABRE catalyst T.sub.1=28.91.6 s and 66.57 s, respectively.

[0324] The simultaneous exchange of p-H.sub.2 and [1-.sup.13C]pyruvate on activated Ir(F-IMes) catalyst leads to buildup of .sup.13C hyperpolarization. In that respect, FIG. 13 shows a representative spectrum of .sup.13C-hyperpolarized [1-.sup.13C]-pyruvate with signal enhancement of 86500 fold, corresponding to P.sub.13C of 13.48% obtained via comparison of the NMR signal intensity with a reference sample. The NMR samples contained in 20 mM sodium [1-.sup.13C]pyruvate, 2.6 mM fluorinated SABRE catalyst, and 40 mM dimethyl sulfoxide (DMSO), the mixing field was at 0.4 T and temperature at 0 C. with a parahydrogen pressure and flow at 110 PSI and 90 scc/m, respectively.

[0325] Temperature has a profound effect on the exchange rates of [1-.sup.13C]pyruvate on Complex 3b of FIG. 7. In recent work, Adelabu et al. (Chem Phys Chem, 23, e202100839 (2022)) showed that the monotonic disappearance of free HP resonance at low temperatures happened due to the slow exchange rate of Complex 3b into the free state. At room temperature (e.g., 22 C.), the exchange of [1-.sup.13C]pyruvate with the polarization transfer complex was faster, leading to hyperpolarization of both free and bound 3b species in the expected pyruvate:pre-catalyst ratio. In order to rapidly release the HP pyruvate from 3b, the HP solution was rapidly warmed up then the sample was inserted in the NMR detector (TomHon et al., J. Am. Chem. Soc., 144 (1) 282-287 (2022)). FIG. 14 shows a variable temperature SABRE-SHEATH experiment using the saturated perfluorinated SABRE catalyst of Example 4. The NMR samples (in deuterated methanol) contained in 25 mM sodium [1-.sup.13C]pyruvate, 6 mM perfluorinated SABRE catalyst, and 47 mM dimethyl sulfoxide (DMSO), wherein the mixing field was at 0.4 T, and the parahydrogen pressure and flow rate were set at 110 PSI and 90 scc/m, respectively.

[0326] As demonstrated by FIG. 14, the exchange rate of Complex 3b into the free state is faster even at low temperature, such as 10 C., where most of the HP [1-.sup.13C]pyruvate is in a free state. By decreasing the temperature of .sup.13C SABRE-SHEATH to 0 C., P.sub.13C maximum is achieved. The exchange remains fast enough to build-up preferentially the free HP [1-.sup.13C]pyruvate over Complex 3b.

Example 8

[0327] This example illustrates an exemplary method for isolating hyperpolarized sodium [1-.sup.13C]pyruvate, which includes extraction and filtration.

[0328] Hyperpolarization of sodium [1-.sup.13C]pyruvate was performed using SABRE in SHield Enables Alignment Transfer to Heteronuclei (SABRE-SHEATH) tailored for the .sup.13C nucleus using dimethyl sulfoxide (DMSO) as a co-ligand, [IrCl(COD)(F-IMes)] SABRE catalyst, and parahydrogen enriched to about 70 to 95% in deuterated methanol-d.sub.4 solvent, as described in Examples 6 and 7. The SABRE samples were prepared in 0.5 mL CD.sub.3OD, using 30 mM sodium [1-.sup.13C]pyruvate, 2.6 mM perfluorinated SABRE catalyst of Example 4, and 35 mM dimethyl sulfoxide (DMSO). The parahydrogen flow rate was established at 90 scc/m and pressurized to 8 bars, the mixing field was 0.4 T, and the temperature was 0 C.

[0329] After the hyperpolarization procedure was completed, the sample was rapidly removed from the 0.40 T field, depressurized, and 20% in volume (125 L) of D.sub.2O was added to the solution to precipitate the perfluorinated SABRE catalyst. The resulting mixture was transferred into a 1 mL plastic syringe mounted to a Luer-locked filter (Waters Oasis Prime HLB Plus Light Cartridge (Part Number: 186008866), and the aqueous solution was guided through the filter into a 5 mm NMR tube, already located into the adjacent 1.8 T benchtop NMR spectrometer. The whole procedure took about 1.15 to 1.30 minutes and no HP .sup.13C signal was observed in any sample. The relaxation study presented above indicates that [1-.sup.13C]-T.sub.1 relaxation time of pyruvate at earth field was substantially shorter (e.g., [1-.sup.13C]-T.sub.1=28.91.6 s at Earth's field). Automation and faster solution transfer should allow the observation of HP [1-.sup.13C]-pyruvate signal in aqueous solutions.

Example 9

[0330] This example illustrates an exemplary method for isolating hyperpolarized sodium [1-.sup.13C]pyruvate, which includes extraction by precipitation with organic solvent.

[0331] Precipitation and redissolution of HP [1-.sup.13C]pyruvate, which takes place in the same NMR tube where hyperpolarization, was performed (Schmidt et al., ACS Sensors, 7(11), 3430-3439 (2022)). The SABRE samples were prepared in CD.sub.3OD, using between 20 and 30 mM sodium [1-.sup.13C]pyruvate, 7.5 mM fluorinated SABRE catalyst, and 50 mM dimethyl sulfoxide (DMSO), as described in Examples 6 and 7. 100 L of this solution was transferred into 5 mm NMR tube and exposed to the SABRE-SHEATH hyperpolarization conditions with the same set-up and optimum conditions described in Examples 6 and 7. The solution was located inside a 3-layer mu-metal of 3 I.D. and 9 depth to shield external magnetic fields, combined with a custom-made solenoid to generate a static magnetic field B.sub.0 of 0.4 T. The NMR tubes were pressurized (110 psi, i.e., approximately 8 bar total pressure) with p-H.sub.2 bubbling through the solution at a flow of 90 scc/m to activate the catalyst and to .sup.13C-hyperpolarize the sodium [1-.sup.13C]pyruvate solution. Activation of the catalyst took place for 15 min at ambient temperature and magnetic field. For polarization build-up, the sample was placed in the static magnetic field (typically about 0.4 T) and a water bath to regulate the reaction temperature at 0 C. After polarization, the NMR tube was rapidly transferred inside the NMR spectrometer at 1.8 T and kept at room temperature. The precipitation of pyruvate is performed after depressurization by adding 400 L of ethyl acetate (EtOAc) to the HP solution and redissolved by adding 300 L D.sub.2O to reconstitute the pyruvate in water.

[0332] The NMR spectrum was acquired immediately after reconstitution in water using a 1.8 T benchtop NMR, and the results are set forth in the top spectrum of FIG. 15. In addition, the bottom spectrum of FIG. 15 shows a single-scan thermally polarized .sup.13C signal from 4 M sodium [1-.sup.13C] acetate using similar acquisition parameters.

[0333] In addition, the .sup.13C-pyruvate concentrations were determined by LCMS using a calibration curve for naturally occurring isotopic pyruvate. The pyruvate aqueous samples were further analyzed by ICP-MS (inductively coupled plasma Multi-Element Scan) for Iridium elemental content after the reconstitution SABRE-SHEATH methodology. The Iridium content was determined to be only about 150 ppb to about 300 ppm.

Example 10

[0334] This example illustrates a method of the synthesis of 2,2,2-trifluoro-N-(4-iodo-2,6-dimethylphenyl) acetamide:

##STR00028##

[0335] To a stirring solution of 2,6-diisopropylaniline (4.92 mL, 40.00 mmol, 1.0 equiv) in diethyl ether (50 mL) were added iodine (11.17 g, 44.00 mmol, 1.1 equiv) and a saturated sodium bicarbonate solution (30 mL). The solution was stirred at room temperature for 3 hours and gas evolution was observed. Excess iodine was destroyed by addition of sodium thiosulfate (1.33 g, 8.40 mmol). The phases were separated, and the aqueous phase was further extracted with diethyl ether (220 mL). The combined organic phases were washed with water (200 mL) and saturated solution of sodium thiosulfate. The organic phase was evaporated to dryness in vacuo to yield the product as a brown oil which slowly became solid under vacuum.

[0336] Hexane was added to dissolve product and the solution is filtered with Celite and evaporated and dried under vacuum. No further purification was necessary. .sup.1H NMR (400 MHz, CDCl.sub.3): =7.14 (s, 2H), 4.45 (s, 2H), 2.04 (s, 6H).

Example 11

[0337] This example illustrates a method of synthesis of N-(2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-tridecafluorooct-1-en-1-yl)phenyl)-2,2,2-trifluoroacetamide:

##STR00029##

[0338] In a glove box, palladium (II) acetate (0.16 g, 0.051 equiv, 0.71 mmol), sodium acetate (1.72 g, 1.50 equiv, 21.0 mmol), tricyclohexylphosphane (660 mg, 0.168 equiv, 2.35 mmol), tetrabutylammonium bromide (30 mg, 0.0067 equiv, 93 mol) and 2,2,2-trifluoro-N-(4-iodo-2,6-dimethylphenyl) acetamide (4 g, 0.8 equiv, 0.01 mol) were added to a Schlenk flask with 10 mL of dimethyl formamide. The Schlenk flask was warmed to 90 C., then 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-tridecafluorooct-1-ene (4.84 g, 1 equiv, 14.0 mmol) was added to the reaction mixture and further heated to 120 C. The solution was stirred for 19 hours. After cooling, the mixture was filtered through Celite and washed with diethyl ether (50 mL). Water (50 mL) and diethyl ether (30 mL) were added, the organic phase was separated, and aqueous phase was extracted with Et.sub.2O (315 mL). The combined organic layers were dried over anhydrous MgSO.sub.4 and concentrated under reduced pressure to afford the crude product. Purification by column chromatography (hexane/DCM 4:1) gave fluoroamide N-(2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-tridecafluorooct-1-en-1-yl)phenyl)-2,2,2-trifluoroacetamide, which was further crystallized (5 g, 70%, white needles).

Example 12

[0339] This example illustrates a synthesis of N-(2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-tridecafluorooctyl)phenyl)-2,2,2-trifluoroacetamide:

##STR00030##

[0340] To a solution of N-(2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-tridecafluorooct-1-en-1-yl)phenyl)-2,2,2-trifluoroacetamide (0.40 g, 0.70 mmol) in ethyl acetate (10 mL) in a glass autoclave, 10% Pd/C (0.08 g, 0.07 mmol) was added. The autoclave was evacuated, filled with hydrogen gas to 500 kPa and stirred for 5 hours at room temperature. The mixture was filtered through Celite and washed with EtOAc (30 mL). The solvent was removed on vacuum rotary evaporator to afford N-(2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-tridecafluorooctyl)phenyl)-2,2,2-trifluoroacetamide.

Example 13

[0341] This example illustrates a synthesis of 2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-tridecafluorooctyl) aniline:

##STR00031##

[0342] To a solution of N-(2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-tridecafluorooctyl)phenyl)-2,2,2-trifluoroacetamide (0.14 g, 250 mol) in n-butanol (1.5 mL), sodium hydroxide (0.10 g, 250 mmol) was added and the reaction mixture was heated to 110 C. for 21 hours. After cooling to room temperature, water (4 mL) and ethyl acetate (4 mL) were added and the organic phase was separated, washed with 1M solution of HCl (4 mL), saturated solution of NaHCO.sub.3 (4 mL), and brine (4 mL). The aqueous phase was neutralized and extracted with ethyl acetate (3 times x 4 mL). The organic layers were combined and dried over anhydrous magnesium sulfate and concentrated under reduced pressure to afford 2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-tridecafluorooctyl) aniline (0.50 g, 92%, brown crystals).

Example 14

[0343] This example illustrates a synthesis of N,N-Bis [2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-tridecafluorooctyl)phenyl]ethane-1,2-diimine:

##STR00032##

[0344] To the solution of 2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-tridecafluorooctyl) aniline (0.5 g, 1 mmol) in ethanol (5 mL), 40% aqueous solution of glyoxal (0.1 mL, 1 mmol) and catalytic amount of formic acid (few drops) were added. The reaction mixture was stirred for 20 hours at room temperature, during which yellow precipitate was formed. The solid was filtered and washed with cold ethanol (35 mL) to give clean N,N-bis(2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-tridecafluorooctyl)phenyl) ethane-1,2-diimine (0.2 g, 20%, yellow powder).

Example 15

[0345] This example illustrates a synthesis of 1,3-bis(2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-tridecafluorooctyl)phenyl)-1H-imidazol-3-ium-2-ide, chloride salt:

##STR00033##

[0346] A flask was charged with N,N-bis(2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,9,10,10,10-tridecafluorooctyl)phenyl) ethane-1,2-diimine (2.40 g, 2.08 mmol) and tetrahydrofuran (80 mL). The mixture was cooled to 0 C. and suspension of paraformaldehyde (262 mg, 2.91 mmol) and conc. HCl (112 mg, 3.12 mmol) in dioxane (0.78 mL) was slowly added. The mixture was heated to reflux overnight. Purification was carried out by column chromatography. .sup.1H NMR (400 MHZ, CDCl.sub.3) 2.07, 2.55, 2.92, 7.37, 8.28, 9.65. MS (ESI) m/z (%): 1168.8 [MTFA].sup.+ (100).

Example 16

[0347] This example illustrates a synthesis of a fluorinated SABRE catalyst in accordance with an aspect of the invention.

##STR00034##

[0348] Potassium tert-butoxide (2.5 eq.) was added to a stirred solution of 1,3-bis(2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-tridecafluorooctyl)phenyl)-1H-imidazol-3-ium-2-ide, chloride (2.2 equiv) in tetrahydrofuran at room temperature in a glove box. The resulting suspension was stirred for 30 min. A solution of [Ir(COD)Cl].sub.2 (1.0 eq.) was added and the resulting solution was stirred at room temperature for 2 hours. The solvent was removed under reduced pressure to give the crude product and dried overnight under vacuum. This sample was purified with flash chromatography DCM/hexane (4:1) to obtain the fluorinated SABRE catalyst. MS (ESI) m/z (%): 1469 [MCl].sup.+ (100).

Example 17

[0349] This example illustrates the hyperpolarization of sodium pyruvate using the SABRE catalyst in accordance with an aspect of the invention, as shown in Scheme 3.

Scheme 3. Hyperpolarization of [1-.sup.13C]Pyruvate Using the Perfluorinated SABRE Catalyst of Example 16 with Dimethyl Sulfoxide as Co-Ligand.

##STR00035##

[0350] In the reaction scheme above, the efficient hyperpolarization transfer from p-H.sub.2-derived hydrides to the .sup.13C nuclear spin of [1-.sup.13C]pyruvate was attained by performing SABRE in sub-microtesla magnetic fields using SABRE in SHield Enables Alignment Transfer to Heteronuclei (SABRE-SHEATH) using a solution mixture of [IrCl(H).sub.2(DMSO).sub.2(F-IMes)], [1-.sup.13C]pyruvate) and p-H.sub.2 in deuterated methanol.

[0351] The SABRE samples were prepared in CD.sub.3OD, using 40 mM sodium [1-.sup.13C]pyruvate, 6.6 mM perfluorinated SABRE catalyst of Example 16, and 50 mM dimethyl sulfoxide (DMSO), as described in Examples 6 and 7. The SABRE samples were exposed to the SABRE-SHEATH hyperpolarization conditions with the same set-up and optimum conditions described in Examples 6 and 7. The NMR tubes were pressurized (110 psi, i.e., approximately 8 bar total pressure) with p-H.sub.2 bubbling through the solution at a flow of 90 scc/m to activate the catalyst and to .sup.13C-hyperpolarize the sodium [1-.sup.13C]pyruvate solution. Activation of the catalyst took place for about 15 minutes at ambient temperature and magnetic field. For polarization build-up, the sample was placed in the magnetic field (typically about 0.4 T) and a water bath at 5 C. to regulate the reaction temperature. The spectrum was acquired immediately following manual sample transfer to a 1.8 T benchtop NMR after 5 seconds, and the results are set forth in the top spectrum of FIG. 16. In addition, the bottom spectrum of FIG. 16 shows a single-scan thermally polarized .sup.13C signal from 4 M sodium [1-.sup.13C] acetate using similar acquisition parameters. As is apparent from the results set forth in FIG. 16, the signal enhancement is &16900 and polarization is about P(.sup.13C)2.17%.

Example 18

[0352] This example illustrates a method of synthesis of N-(2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooct-1-en-1-yl)phenyl)-2,2,2-trifluoroacetamide:

##STR00036##

[0353] In a glove box, palladium (II) acetate (0.16 g, 0.051 equiv, 0.71 mmol), sodium acetate (1.72 g, 1.50 equiv, 21.0 mmol), tricyclohexylphosphane (660 mg, 0.168 equiv, 2.35 mmol), tetrabutylammonium bromide (30 mg, 0.0067 equiv, 93 mol) and 2,2,2-trifluoro-N-(4-iodo-2,6-dimethylphenyl) acetamide (4 g, 0.8 equiv, 0.01 mol) were added to a Schlenk flask with 10 mL of dimethyl formamide. The Schlenk flask was warmed to 90 C., then 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooct-1-ene (4.84 g, 1 equiv, 14.0 mmol) was added to the reaction mixture and further heated to 120 C. The solution was stirred for 19 hours. After cooling, the mixture was filtered through Celite and washed with diethyl ether (50 mL). Water (50 mL) and diethyl ether (30 mL) were added, the organic phase was separated, and aqueous phase was extracted with Et.sub.2O (315 mL). The combined organic layers were dried over anhydrous MgSO.sub.4 and concentrated under reduced pressure to afford the crude product. Purification by column chromatography (hexane/DCM 4:1) gave fluoroamide N-(2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooct-1-en-1-yl)phenyl)-2,2,2-trifluoroacetamide, which was further crystallized (5 g, 70%, white needles).

Example 19

[0354] This example illustrates a synthesis of 2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl) aniline:

##STR00037##

[0355] To a solution of N-(2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooct-1-en-1-yl)phenyl)-2,2,2-trifluoroacetamide (0.14 g, 250 mol) in n-butanol (1.5 mL), sodium hydroxide (0.10 g, 250 mmol) was added and the reaction mixture was heated to 110 C. for 21 hours. After cooling to room temperature, water (4 mL) and ethyl acetate (4 mL) were added and the organic phase was separated, washed with 1M solution of HCl (4 mL), saturated solution of NaHCO.sub.3 (4 mL), and brine (4 mL). The aqueous phase was neutralized and extracted with ethyl acetate (3 times4 mL). The organic layers were combined and dried over anhydrous magnesium sulfate and concentrated under reduced pressure to afford 2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl) aniline (0.50 g, 92%, brown crystals).

Example 20

[0356] This example illustrates a synthesis of N,N-Bis [2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooct-1-en-1-yl)phenyl]ethane-1,2-diimine:

##STR00038##

[0357] To the solution of 2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooct-1-en-1-yl) aniline (0.5 g, 1 mmol) in ethanol (5 mL), 40% aqueous solution of glyoxal (0.1 mL, 1 mmol) and catalytic amount of formic acid (few drops) were added. The reaction mixture was stirred for 20 hours at room temperature, during which yellow precipitate was formed. The solid was filtered and washed with cold ethanol (35 mL) to give clean N,N-bis(2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)phenyl) ethane-1,2-diimine (0.2 g, 20%, yellow powder).

Example 21

[0358] This example illustrates a synthesis of 1,3-bis(2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooct-1-en-1-yl)-1H-imidazol-3-ium-2-ide, chloride salt:

##STR00039##

[0359] A flask was charged with N,N-bis(2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooct-1-en-1-yl)phenyl) ethane-1,2-diimine (2.40 g, 2.08 mmol) and tetrahydrofuran (80 mL). The mixture was cooled to 0 C. and suspension of paraformaldehyde (262 mg, 2.91 mmol) and conc. HCl (112 mg, 3.12 mmol) in dioxane (0.78 mL) was slowly added. The mixture was heated to reflux overnight. Purification was carried out by column chromatography. .sup.1H NMR (400 MHZ, CDCl.sub.3) 2.27, 6.71, 7.32, 7.36, 7.67, 8.16, 9.59 ppm. .sup.19F NMR (400 MHZ, CDCl.sub.3) 82.43, 112.52, 122.59, 123.89, 124.17, 127.33 ppm. MS (ESI) m/z (%): 964.8 [M+H].sup.+ (100).

Example 22

[0360] This example illustrates a synthesis of a fluorinated SABRE catalyst in accordance with an aspect of the invention.

##STR00040##

Potassium tert-butoxide (2.5 eq.) was added to a stirred solution of 1,3-bis(2,6-dimethyl-4-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooct-1-en-1-yl)phenyl)-1H-imidazol-3-ium-2-ide, chloride (2.2 equiv) in tetrahydrofuran at room temperature in a glove box. The resulting suspension was stirred for 30 min. A solution of [Ir(COD)Cl].sub.2 (1.0 eq.) was added and the resulting solution was stirred at room temperature for 2 hours. The solvent was removed under reduced pressure to give the crude product and dried overnight under vacuum. This sample was purified with flash chromatography DCM/hexane (4:1) to obtain the fluorinated SABRE catalyst. MS (ESI) m/z (%): 1266 [MCl].sup.+ (100).

Example 23

[0361] This example illustrates the hyperpolarization of sodium pyruvate using the SABRE catalyst in accordance with an aspect of the invention, as shown in Scheme 4.

Scheme 4. Hyperpolarization of [1-.sup.13C]Pyruvate Using the Shown Perfluorinated SABRE Catalyst with Dimethyl Sulfoxide as Co-Ligand.

##STR00041##

[0362] In the reaction scheme above, the efficient hyperpolarization transfer from p-H.sub.2-derived hydrides to the .sup.13C nuclear spin of [1-.sup.13C]pyruvate was attained by performing SABRE in sub-microtesla magnetic fields using SABRE in SHield Enables Alignment Transfer to Heteronuclei (SABRE-SHEATH) using a solution mixture of [IrCl(H).sub.2(DMSO).sub.2(F-IMes)], [1-.sup.13C]pyruvate) and p-H.sub.2 in deuterated methanol.

[0363] The SABRE samples were prepared in CD.sub.3OD, using 20 mM sodium [1-.sup.13C]pyruvate, 7.6 mM perfluorinated SABRE catalyst shown in Scheme 4, and 50 mM dimethyl sulfoxide (DMSO), as described in Examples 6 and 7. The SABRE samples were exposed to the SABRE-SHEATH hyperpolarization conditions with the same set-up and optimum conditions described in Examples 6 and 7. The NMR tubes were pressurized (110 psi, i.e., approximately 8 bar total pressure) with p-H.sub.2 bubbling through the solution at a flow of 90 scc/m to activate the catalyst and to .sup.13C-hyperpolarize the sodium [1-.sup.13C]pyruvate solution. Activation of the catalyst took place for about 15 minutes at ambient temperature and magnetic field. For polarization build-up, the sample was placed in the magnetic field (typically about 0.4 T) and a water bath at 5 C. to regulate the reaction temperature. The spectrum was acquired immediately following manual sample transfer to a 1.8 T benchtop NMR after 5 seconds, and the results are set forth in the top spectrum of FIG. 17. In addition, the bottom spectrum of FIG. 17 shows a single-scan thermally polarized .sup.13C signal from 4 M sodium [1-.sup.13C] acetate using similar acquisition parameters. As is apparent from the results set forth in FIG. 17, the signal enhancement is 19000 and polarization is about P (.sup.13C)4.91%.

Example 24

[0364] This example illustrates a method of hyperpolarizing a [1-.sup.13C]pyruvate in accordance with an aspect of the invention, using a fluorous mixture instead of only deuterated methanol.

[0365] The hyperpolarization procedure of Example 6 was repeated using a mixture of nonafluorobutyl methyl ether (NFBME) and deuterated methanol instead of only deuterated methanol.

[0366] The fluorinated SABRE catalyst activation took less than 25 minutes, with the .sup.13C polarization percentage shown in FIG. 18, and is performed by bubbling 95% p-H.sub.2 at a flow rate of 90 standard cubic centimeters per minute (scc/m) at 8 atm p-H.sub.2 partial pressure. The NMR samples contained about 25 mM sodium [1-.sup.13C]pyruvate, 7.4 mM perfluorinated SABRE catalyst of Example 4, and 40 mM dimethyl sulfoxide (DMSO) in 0.3 mL NFBME and 0.2 mL MeOD with the mixing field at 0.4 T and a temperature of 0 C.

Example 25

[0367] This example demonstrates the effects on hyperpolarization of [1-.sup.13C]pyruvate in a fluorous mixture, exhibited by changes in parahydrogen pressure and flow rate, as well as the effect of magnetic transfer field. In addition, the relaxation dynamics of the [1-.sup.13C]pyruvate were also studied.

[0368] Hyperpolarization of [1-.sup.13C]pyruvate was repeated using SABRE in SHield Enables Alignment Transfer to Heteronuclei (SABRE-SHEATH), as described in Example 24 above, and the effects of parahydrogen flow rate, as well as the effect of magnetic transfer field, were studied.

[0369] p-H.sub.2 flow rate was evaluated and the polarization percentage results are set forth in FIG. 19. The NMR samples contained about 22 mM sodium [1-.sup.13C]pyruvate, 7.4 mM perfluorinated SABRE catalyst of Example 4, and 45 mM dimethyl sulfoxide (DMSO) in 0.3 mL NFBME and 0.2 mL MeOD with the mixing field at 0.4 T and a temperature of 0 C. As is apparent from the results set forth in FIG. 19, as the parahydrogen flow rate increased, the polarization percentage also increased.

[0370] The magnetic field in the micro Tesla regime was evaluated and the .sup.13C polarization transfer magnetic field at 0 C. is set forth in FIG. 20. The NMR samples contained 22 mM sodium [1-.sup.13C]pyruvate, 7.4 mM perfluorinated SABRE catalyst of Example 4, and 46 mM dimethyl sulfoxide (DMSO) in 0.2 mL NFBME and 0.2 mL MeOD. The p-H.sub.2 flow rate and pressure were 50 ssc/m and 110 PSI, respectively. As is apparent from the results set forth in FIG. 20, the best polarization transfer occurs at a mixing field between 0.3 T and 0.5 T. The optimum mixing field is 0.4 T.

[0371] As is apparent from the results set forth in FIGS. 21A and 21B, the relaxation dynamics of [1-.sup.13C]-pyruvate show that the total P.sup.13C (bound+free) build-up time (T.sub.b=3.00.8 s) is substantially shorter than the corresponding Ti value of 11.31.3 s, which allows to reach P.sub.13C levels up to 6.02%. In addition, relaxation dynamics at earth field and 1.8 T are about the same as a non-fluorinated SABRE catalyst T1=9.01.9 s and 16.01.4 s, respectively.

[0372] The simultaneous exchange of p-H.sub.2 and [1-.sup.13C]pyruvate on activated Ir(F-IMes) catalyst leads to buildup of .sup.13C hyperpolarization. In that respect, the top spectrum of FIG. 22 shows a representative spectrum of .sup.13C-hyperpolarized [1-.sup.13C]-pyruvate with signal enhancement of 38600 fold, corresponding to P.sub.13C of 6.02% obtained via comparison of the NMR signal intensity to a reference sample (i.e., the bottom spectrum of FIG. 22, which shows a single-scan thermally polarized .sup.13C signal from 4 M sodium [1-.sup.13C] acetate using similar acquisition parameters). The NMR samples contained 23 mM sodium [1-.sup.13C]pyruvate, 7.4 mM perfluorinated SABRE catalyst of Example 4, and 46 mM dimethyl sulfoxide (DMSO) in 0.2 mL NFBME and 0.2 mL MeOD. The p-H.sub.2 flow rate and pressure were 90 ssc/m and 110 PSI, respectively, with the mixing field at 0.4 T and a temperature of 0 C.

[0373] Temperature has a profound effect on the exchange rates of [1-.sup.13C]pyruvate on Complex 3b of FIG. 7. In recent work, Adelabu et al. (Chem Phys Chem, 23, e202100839 (2022)) showed that the monotonic disappearance of free HP resonance at low temperatures happened due to the slow exchange rate of Complex 3b into the free state. At room temperature (e.g., 22 C.), the exchange of [1-.sup.13C]pyruvate with the polarization transfer complex was faster, leading to hyperpolarization of both free and bound 3b species in the expected pyruvate: pre-catalyst ratio. In order to rapidly release the HP pyruvate from 3b, the HP solution was rapidly warmed up then the sample was inserted in the NMR detector (TomHon et al., J. Am. Chem. Soc., 144(1) 282-287 (2022)). FIG. 23 shows a variable temperature SABRE-SHEATH experiment using the saturated perfluorinated SABRE catalyst of Example 4. The NMR samples (in nonafluorobutyl methyl ether (NFBME) and deuterated methanol) contained in 23 mM sodium [1-.sup.13C]pyruvate, 7.4 mM perfluorinated SABRE catalyst of Example 4, and 46 mM dimethyl sulfoxide (DMSO), wherein the mixing field was at 0.4 T, and the parahydrogen pressure and flow rate were set at 110 PSI and 90 scc/m, respectively.

[0374] As demonstrated by FIG. 23, the exchange rate of Complex 3b into the free state is faster even at low temperature, such as 10 C., where most of the HP [1-.sup.13C]pyruvate is in a free state. By decreasing the temperature of .sup.13C SABRE-SHEATH to 0 C., P.sub.13C maximum is achieved. The exchange remains fast enough to build-up preferentially the free HP [1-.sup.13C]pyruvate over Complex 3b.

Example 26

[0375] This example illustrates an exemplary method for isolating hyperpolarized sodium [1-.sup.13C]pyruvate, which includes biphasic extraction with an aqueous phase and a fluorinated phase.

[0376] The hyperpolarization procedure of Example 6 was repeated using a mixture of nonafluorobutyl methyl ether (NFBME) and deuterated methanol instead of only deuterated methanol. The SABRE sample was prepared with 23 mM sodium [1-.sup.13C]pyruvate, 7.4 mM perfluorinated SABRE catalyst of Example 4, and 46 mM dimethyl sulfoxide (DMSO) in 0.2 mL NFBME and 0.2 mL MeOD, wherein the mixing field was at 0.4 T, and the parahydrogen pressure and flow rate were set at 110 PSI and 90 scc/m, respectively.

[0377] After the hyperpolarization procedure was completed, the sample was rapidly removed from the 0.40 T field and transferred inside the NMR spectrometer at 1.8 T at room temperature. The NMR sample was depressurized and 400 L of D.sub.2O was added to the solution in order to drive the hyperpolarized sodium [1-.sup.13C]pyruvate into the aqueous phase. The pyruvate signal in the aqueous phase was collected, but the separation led to the formation of an emulsion, indicating that both bound and free pyruvate are present. See FIG. 24. In that respect, the top spectrum of FIG. 24 shows a representative spectrum of .sup.13C-hyperpolarized [1-.sup.13C]-pyruvate with signal enhancement of 10800 fold, corresponding to P.sub.13C of 1.68% obtained via comparison of the NMR signal intensity to a reference sample (i.e., the bottom spectrum of FIG. 24, which shows a single-scan thermally polarized .sup.13C signal from 4 M sodium [1-.sup.13C] acetate using similar acquisition parameters).

[0378] The aqueous phase containing the sodium [1-.sup.13C]pyruvate was evacuated and tested for iridium content and pyruvate concentration. The ICP-MS study showed a content of 637 ppb of iridium and the LCMS showed about 50-75% of the sodium [1-.sup.13C]pyruvate concentration was collected after filtration.

[0379] The fluorous mixture containing the perfluorinated SABRE catalyst in NFBME and MeOD was re-used for further sodium [1-.sup.13C]pyruvate hyperpolarization. After evacuation of the water phase, a solution containing 23 mM sodium [1-.sup.13C]pyruvate and 47 mM dimethyl sulfoxide in 0.2 mL CD.sub.3OD was added to the fluorous mixture containing the perfluorinated SABRE catalyst from 4 days earlier. The hyperpolarization of sodium [1-.sup.13C]pyruvate was repeated, and showed a polarization of the [1-.sup.13C]pyruvate with a signal enhancement of 3090 fold, corresponding to P.sub.13C of 0.48%, which was obtained via comparison of the NMR signal intensity to a reference sample, as shown in FIG. 25. The polarization of [1-.sup.13C]pyruvate is repeatable and showed about the same polarization level, demonstrating that the perfluorinated SABRE catalyst remains active for at least 4 days after initial use.

Example 27

[0380] This example illustrates a synthesis of 1,3-dimesityl-4,5-bis(2-(perfluorophenyl)propyl)-4,5-dihydro-1H-imidazol-3-ium, triflate salt:

##STR00042##

which was prepared in accordance with the synthesis sequence set forth in FIG. 26.

[0381] 4-Pentafluorophenylbutanal (3). To a solution of the alcohol (2) (4.8 g, 20.0 mmol) in DCM (40 mL), was added Dess-Martin periodinane (16.96 g, 40.0 mmol) portionwise at 0 C. while being stirred under argon (5 minutes). The reaction was continued until the starting alcohol was consumed (2 hours). The resulting solution was concentrated to about 10.0 mL and adsorbed onto 10.0 g of silica and dried to a free flowing powder. The silica with the crude product was applied to a silica column (120.0 g), and elution with 5% ethyl acetate in hexanes yielded the product as colorless oil. Yield: 3.33 g (70%). .sup.1H NMR (CDCl.sub.3): .sup.1H NMR (400 MHZ, CDCl.sub.3) 9.71 (t, J=1.3 Hz, 1H), 2.69 (tt, J=7.9, 1.8 Hz, 2H), 2.44 (td, J=7.3, 1.2 Hz, 2H), 1.86 (p, J=7.3 Hz, 2H). .sup.13C NMR (101 MHz, CDCl.sub.3) 200.89, 42.81, 21.49.

[0382] 1,2,3,4,5-Pentafluoro-6-(4-iodobutyl)benzene (4). An ice-cooled solution of the alcohol (2) (16.0 g, 66.67 mmol) was stirred with imidazole (5.89 g, 86.67 mmol) and triphenylphosphine (20.96 g, 80.0 mmol) in DCM (100 mL) under argon. Iodine (20.32 g, 80.0 mmol) was added portionwise over a period of 15 minutes at 0 C. while being vigorously stirred until a slight yellow color persisted. The reaction mixture was diluted with hexanes (300 mL) and filtered. The filtrate was washed with saturated sodium thiosulfate (350 mL), water (3100 mL), and dried with sodium sulfate. The clear solution was filtered and concentrated to an oil that was chromatographed over silica gel (220 g). Elution with hexanes yielded compound (4) as colorless oil. Yield: 21.0 g (90%). .sup.1H NMR (400 MHZ, cdcl.sub.3) 3.20 (t, J=6.8 Hz, 1H), 2.73 (tt, J=7.5, 1.8 Hz, 1H), 1.86 (dq, J=8.6, 6.8 Hz, 1H), 1.76-1.66 (m, 1H). .sup.13C NMR (101 MHz, cdcl.sub.3) 37.84, 30.01, 21.27, 5.39.

[0383] Iodo-(4-(pentafluorophenyl)butyl)triphenyl-15-phosphane (5). A solution of the iodobutane (4) (21.0 g, 60.0 mmol) and triphenylphosphine (17.29 g, 66.0 mmol) was refluxed under argon for 24 hours. The precipitated solid was filtered and washed with anhydrous ether and dried under high vacuum for 20 hours. Yield: 33.78 g (92%). .sup.1H NMR (400 MHZ, CDCl.sub.3) 7.73 (m, 15H), 3.92, 3.86 (m, 2H), 2.76, 2.74 (m, 2H), 2.07, 2.025 (m, 2H), 1.6 (m, 2H). .sup.13C NMR (101 MHz, CDCl.sub.3) 135.23, 135.20, 133.75, 133.65, 130.65, 130.53, 118.32, 117.46, 29.43, 29.27, 23.05, 22.55, 21.78, 21.74, 21.66.

[0384] Compound 6. To a solution of the phosphonium salt (5) (6.79 g, 11 mmol) in anhydrous THF (40 mL) was added potassium tert-butoxide in THF (2M, 12.5 mL, 25.0 mmol) dropwise and stirred under argon for 30 minutes. Aldehyde (3) (2.2 g, 9.24 mmol) in THF (5 mL) was added dropwise at room temperature and stirred for 3 hours. The solution was concentrated, and purified on flash silica (120 g). Elution with hexanes yielded the product as a colorless oil as mixture of cis/trans isomers (90:10). Yield: 3.2 g (72%). .sup.1H NMR (400 MHZ, CDCl.sub.3) 5.41 (m, 2H), 2.72, 2.68 (m, 4H), 2.12, 2.10, 2.06 (m, 4H), 1.64 (m, 4H). .sup.13C NMR (101 MHz, CDCl.sub.3) 129.46, 29.12, 26.76, 21.94

[0385] Compound 7. Olefin (6) (3.6 g, 8.1 mmol) in acetone (20 mL) and water (0.5 mL) was cooled to 0 C., and dibromamine-T (2.93 g, 8.91 mmol, Org. Biomol. Chem., 8, 1424-1430 (2010)) was added with vigorous stirring. After the addition, the solution was brought to room temperature and stirred until the starting material disappeared (30 minutes). The solution was quenched with solid sodium thiosulfate (2.0 g) and stirred until the color of bromine was completely discharged. The mixture was concentrated under reduced pressure, and the residue was diluted with water (50 mL) and extracted with EtOAc (330 mL). The combined organic layers were dried (MgSO.sub.4), filtered, and concentrated under reduced pressure. The residue was chromatographed over flash silica (80 g) and eluted with 10% EtOAc in hexanes to yield the bromohydrin (7) as mixture of diastereomers and as colorless oil. Yield: 2.41 g (55%). .sup.1H NMR (400 MHz), CDCl.sub.3) 4.02 (m, 1H), 3.48 (m, 1H), 2.73 (4H, CH.sub.2C.sub.6F.sub.5), 1.6-2.0 (m, 9H, CH.sub.2 and OH)). .sup.13C NMR (101 MHZ, CDCl.sub.3) 143.76, 138.35, 129.62, 126.82, 59.74, 57.12, 35.29, 34.50, 27.39, 25.48, 21.74, 21.34.

[0386] Compound 8. The bromohydrin (7) (2.2 g, 4.06 mmol) was dissolved in DCM (10.0 mL) and stirred with 5.0 g of molecular sieves. Dess-Martin reagent (3.44 g, 8.12 mmol) was added and stirred until the starting material was completely consumed (30 minutes). The whole mixture was adsorbed onto flash silica (20.0 g) and dried to a free flowing powder. The silica with the crude product was loaded onto a flash silica (80.0 g) column and eluted with 0 to 20% EtOAc in hexanes over 20 minutes (80.0 mL/min; elution rate). Bromoketone (8) was eluted at 5% EtOAc in hexanes as a colorless syrup. Yield: 1.82 g (83%). .sup.1H NMR (400 MHZ, CDCl.sub.3) 4.25 (dd, J=8.3, 6.0 Hz, 1H), 2.94-2.81 (m, 1H), 2.80-2.68 (m, 4H), 2.67-2.52 (m, 1H), 2.09-1.86 (m, 4H), 1.86-1.59 (m, 2H). .sup.13C NMR (101 MHz, CDCl.sub.3) 202.53, 52.19, 38.18, 32.31, 26.87, 23.21, 21.62, 21.45.

[0387] Compound 9. Sodium bicarbonate (0.56 g, 6.68 mmol) was added to a stirred solution of bromoketone (8) (1.8 g, 3.34 mmol) in anhydrous acetonitrile (10.0 mL). Trimethylaniline formamidine (0.94 g, 3.34 mmol) was then added to the stirred solution as a solid, and the reaction mixture was heated to 60 C. with the exclusion of moisture. After the consumption of the bromoketone (70 hours), the reaction mixture was filtered, concentrated under reduced pressure, and chromatographed over flash silica (80 g). Elution with 20% DCM in hexanes yielded the ketoamidine (10) as a colorless syrup. Yield: 1.2 g (49%). 1H NMR (CDCl.sub.3) 6.91 9s, 1H), 6.81 (s, 1H), 6.71 (s, 1H), 6.68 (s, 2H), 4.53 (m, 1H), 3.08 (m, 1H), 2.57 (m, 2h), 2.43 (m, 2H), 2.35 (m, 2H), 2.36 (s, 3h), 2.2 (s, 3H), 2.13 (s, 3H), 2.01 (s, 3H), 1.92 (s, 6H), 1.8 (m, 2H). .sup.13C NMR (101 MHz, CDCl.sub.3) 208.19, 151.90, 138.19, 131.45, 129.47, 128.74, 64.33, 60.38, 41.49, 28.39, 25.50, 22.96, 20.56, 18.44, 18.41, 18.23, 14.18. MS: 739.1 [M+H].

[0388] Compound 11 (triflate salt). To an ice-cooled solution of the keto amidine (0.994 g, 1.35 mmol) in ethanol, lithium borohydride (2M in THF, 0.675 ml, 1.35 mmol) was added and stirred under argon for 24 h at 0-5 C. The reaction mixture was poured into 50 ml of water and extracted with ethyl acetate (350 ml). The combined organic layers were dried (sodium sulfate), and filtered, and concentrated to a paste at room temperature. The above paste was dissolved in 5.0 ml of anhydrous benzene and cooled to 0 C. DIPEA (0.523 g, 4.05 mmol) was added and stirred under argon. Trifluoromethanesulfonic anhydride (1.104 g, 1.34 mmol) was then added dropwise and stirring was continued for 1h. LC/MS indicated the complete consumption of peak corresponding to 741. The mixture was adsorbed onto 10.0 g of silica gel and dried to a free flowing powder. The silica with the crude product was loaded onto an empty loading column placed on the top of a 80.0 g silica column and chromatographed. Elution with 4% MeOH in DCM yielded the product as a mixture of cis/trans isomers and as brown paste. Yield: 0.338 g (33%). .sup.1H NMR (CDCl.sub.3) 8.82 (s, 1H), 6.93 (s, 4H), 4.15 (m, 2H), 2.61 (m, 4H), 2.25, 2.23, 2.21 (3S, 18H), 1.77 (m, 4H), 1.41 (m, 4H). .sup.13C NMR (101 MHZ, CDCl.sub.3) 159.41, 141.00, 135.66, 134.43, 130.60, 129.96, 128.58, 68.76, 66.17, 32.48, 26.91, 24.65, 21.71, 20.97, 18.38, 18.11. MS: 723.0 [M+H].

[0389] All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.

[0390] The use of the terms a and an and the and at least one and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The use of the term at least one followed by a list of one or more items (for example, at least one of A and B) is to be construed to mean one item selected from the listed items (A or B) or any combination of two or more of the listed items (A and B), unless otherwise indicated herein or clearly contradicted by context. The terms comprising, having, including, and containing are to be construed as open-ended terms (i.e., meaning including, but not limited to,) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., such as) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

[0391] Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments can become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.