RUTHENIUM CATALYSTS AND METHODS THEREOF
20260008037 ยท 2026-01-08
Assignee
Inventors
- Matthew Conley (Riverside, CA, US)
- Jessica Rodriguez (Roseville, CA, US)
- Joshua Richardson (Colton, CA, US)
Cpc classification
B01J31/1666
PERFORMING OPERATIONS; TRANSPORTING
B01J31/2273
PERFORMING OPERATIONS; TRANSPORTING
B01J31/1633
PERFORMING OPERATIONS; TRANSPORTING
B01J31/2226
PERFORMING OPERATIONS; TRANSPORTING
B01J2540/225
PERFORMING OPERATIONS; TRANSPORTING
B01J31/2404
PERFORMING OPERATIONS; TRANSPORTING
International classification
B01J31/16
PERFORMING OPERATIONS; TRANSPORTING
B01J31/24
PERFORMING OPERATIONS; TRANSPORTING
Abstract
Certain embodiments of the invention provide a supported cationic Ru catalyst that is highly active in catalyzing olefin metathesis. Certain embodiments of the invention also provide a method of making a supported cationic Ru catalyst described herein, comprising contacting a Ru catalyst with a silylium-capped support.
Claims
1. A catalyst composition comprising a cationic Ruthenium (Ru) catalyst having structure of Formula I: ##STR00044## wherein X is absent, halogen, O(O)CR.sub.t or OR.sub.x, wherein R.sub.t is alkyl or aryl and the alkyl, or aryl is optionally substituted with one or more substituent of hydroxy or halogen (e.g., F); wherein R.sub.x is alkyl, alkanoyl, or aryl, and the alkyl, alkanoyl, or aryl is optionally substituted with one or more substituent of hydroxy or halogen (e.g., F); wherein when X is O(O)CR.sub.t, the one (the non-carbonyl oxygen) or two oxygen(s) of O(O)CR.sub.t is bonded with the Ru; R.sub.1 is aryl (e.g., indenylidene) or (CH)-aryl (e.g., benzylidene), wherein the aryl or (CH)-aryl is optionally substituted with one or more substituent selected from the group consisting of hydroxy, halogen, alkyl, alkoxy, nitro (NO.sub.2), or aryl; and each L is independently O, alkoxy, P(R.sub.a).sub.3, heterocycle, or heteroaryl, one L may be absent, wherein the heterocycle, or heteroaryl is optionally substituted with one or more substituent selected from the group consisting of hydroxy, halogen, alkyl, adamantyl, alkoxy, nitro (NO.sub.2), or aryl that is optionally substituted with one or more alkyl (e.g., mesityl), and wherein R.sub.a is alkyl, cycloalkyl, or aryl that is optionally substituted with one or more alkyl; wherein one L is absent when X is O(O)CR.sub.t and the two oxygen(s) of O(O)CR.sub.t are bonded with the Ru; wherein when X is absent, one L (a bidentate ligand when X is absent) is heterocycle, or heteroaryl substituted with one or more substituent (e.g., alkyl or adamantyl) and the substituent forms a RuC bond with the Ru; wherein Ru, together with the intervening carbon atoms of R.sub.1, and the oxygen atom of O or alkoxy of one L, optionally form a ring (e.g., a five-membered ring); and a support.
2. The catalyst composition of claim 1, wherein the cationic Ru catalyst has structure of Formula Ia: ##STR00045##
3. The catalyst composition of claim 1, wherein the cationic Ru catalyst has structure of Formula Ib: ##STR00046## wherein R.sub.2 is alkyl (e.g., C1-C6 alkyl).
4. The catalyst composition of claim 1, wherein the cationic Ru catalyst has structure of Formula Ic: ##STR00047##
5. The catalyst composition of any one of claims 1-4, wherein each L is independently O, alkoxy, P(R.sub.a).sub.3, or heterocycle.
6. The catalyst composition of any one of claims 1-5, wherein each L is independently selected from the group consisting of O, alkoxy, P(R.sub.a).sub.3, ##STR00048## wherein R.sub.b, R.sub.c, R.sub.d is independently H, alkyl, adamantyl or aryl; and the aryl is optionally substituted with one or more alkyl.
7. The catalyst composition of claim 6, wherein each L is independently selected from the group consisting of O, alkoxy, P(R.sub.a).sub.3, or ##STR00049##
8. The catalyst composition of any one of claims 3 and 5-7, wherein the cationic Ru catalyst has structure of Formula Id or Formula Ie: ##STR00050## wherein R.sub.2 is alkyl (e.g., C1-C6 alkyl).
9. The catalyst composition of claim 8, wherein R.sub.2 is isopropyl.
10. The catalyst composition of any one of claims 6-9, wherein R.sub.b and R.sub.c are each independently phenyl optionally substituted with one or more alkyl.
11. The catalyst composition of claim 10, wherein R.sub.b and R.sub.c are each mesityl (Mes).
12. The catalyst composition of any one of claims 1-11, wherein X is halogen (e.g., Cl, Br, or I), or OR.sub.x.
13. The catalyst composition of any one of claims 1-11, wherein X is O(O)CR.sub.t or OR.sub.x.
14. The catalyst composition of any one of claims 1, 5-7 and 9-13, wherein the cationic Ru catalyst has structure of ##STR00051## wherein substituent Y is selected from the group consisting of hydroxy, halogen, alkyl, alkoxy, nitro (NO.sub.2), or aryl.
15. The catalyst composition of claim 3, wherein the cationic Ru catalyst has structure of ##STR00052##
16. The catalyst composition of claim 1, wherein the cationic Ru catalyst has structure of ##STR00053##
17. The catalyst composition of claim 1, wherein the cationic Ru catalyst has structure of ##STR00054##
18. The catalyst composition of any one of claims 1-17, wherein the support comprises sulfated metal oxide.
19. The catalyst composition of any one of claims 1-17, wherein the support comprises oxide-Aluminum alkoxide (E.sub.xO.sub.y/Al(OR.sup.s).sub.3) having structure of ##STR00055## wherein E is metal or non-metal; x is 1 or 2; and y is 2 or 3, and wherein R.sup.s is alkyl (e.g., C1-C6 or C1-C4 alkyl such as t-butyl) optionally substituted with one or more halogen (e.g., F).
20. The catalyst composition of any one of claim 1-17 or 19, wherein the support comprises silica-aluminum alkoxide SiO.sub.2/Al(OR.sup.s).sub.3, wherein R.sup.s is alkyl optionally substituted with one or more halogen (e.g., F).
21. The catalyst composition of claim 19 or 20, wherein R.sup.s is perfluoro alkyl (e.g., C(CF.sub.3).sub.3).
22. The catalyst composition of claim 21, wherein the silica-aluminum alkoxide (SiO.sub.2/Al(OR.sup.s).sub.3) has structure of ##STR00056##
23. The catalyst composition of any one of claims 18-22, wherein the catalyst composition comprises ion-pair having structure of ##STR00057##
24. A method for catalyzing olefin metathesis, comprising contacting one or more reactant olefin with a catalyst composition according to any one of claims 1-23.
25. The method of claim 24, wherein two identical reactant olefins are coupled to form a product olefin.
26. The method of claim 24, wherein two different reactant olefins are contacted with the catalyst composition.
27. The method of claim 24, wherein the olefin metathesis is cross-metathesis, ring-closing metathesis, or ring-opening metathesis.
28. The method of claim 24, wherein the olefin metathesis is cross-metathesis.
29. The method of claim 24, wherein the olefin metathesis is ethenolysis reaction.
30. A method of making a catalyst composition according to any one of claims 1-23, comprising contacting a Ru compound of Formula II with a silylium on a support, wherein the silylium has structure of .sup.+Si(R.sub.m).sub.3, wherein R.sub.m is alkyl or aryl, and the aryl is optionally substituted with one or more alkyl; and the Ru compound of Formula II is ##STR00058## each X is independently halogen, O(O)CR.sub.t or OR.sub.x, one X may be absent, wherein R.sub.t is alkyl or aryl and the alkyl, or aryl is optionally substituted with one or more substituent of hydroxy or halogen (e.g., F); wherein R.sub.x is alkyl, alkanoyl, or aryl, and the alkyl, alkanoyl, or aryl is optionally substituted with one or more substituent of hydroxy or halogen (e.g., F); wherein when X is O(O)CR.sub.t, the one oxygen of O(O)CR.sub.t is bonded with the Ru, or only one X is O(O)CR.sub.t wherein the two oxygens of O(O)CR.sub.t are bonded with the Ru; R.sub.1 is aryl (e.g., indenylidene) or (CH)-aryl (e.g., benzylidene), wherein the aryl or (CH)-aryl is optionally substituted with one or more substituent selected from the group consisting of hydroxy, halogen, alkyl, alkoxy, nitro (NO.sub.2), or aryl; and each L is independently O, alkoxy, P(R.sub.a).sub.3, heterocycle, or heteroaryl, one L may be absent, wherein the heterocycle, or heteroaryl is optionally substituted with one or more substituent selected from the group consisting of hydroxy, halogen, alkyl, adamantyl, alkoxy, nitro (NO.sub.2), or aryl that is optionally substituted with one or more alkyl (e.g., mesityl), and wherein R.sub.a is alkyl, cycloalkyl, or aryl that is optionally substituted with one or more alkyl; wherein one L is absent when only one X is O(O)CR.sub.t and the two oxygen(s) of O(O)CR.sub.t are bonded with the Ru; wherein when one X is absent, one L (a bidentate ligand when X is absent) is heterocycle, or heteroaryl substituted with one or more substituent (e.g., alkyl or adamantyl) and the substituent forms a RuC bond with the Ru; wherein Ru, together with the intervening carbon atoms of R.sub.1, and the oxygen atom of O or alkoxy of one L, optionally form a ring (e.g., a five-membered ring).
31. The method of claim 30, wherein R.sub.m is isopropyl.
32. The method of claim 30 or 31, wherein the support is acoording to any one of claims 18-22.
33. The method of claim 30, 31 or 32, wherein the silynium on a support has structure of ##STR00059## wherein R.sup.s is alkyl optionally substituted with one or more halogen.
34. The method of any one of claim 30-33, wherein Ru compound has structure of formula IIa, ##STR00060##
35. The method of any one of claim 30-33, wherein Ru compound has structure of formula IIb, ##STR00061## wherein R.sub.2 is alkyl (e.g., isopropyl).
36. The method of any one of claim 30-33, wherein Ru compound has structure of formula IIc, ##STR00062##
37. The method of any one of claim 30-33, wherein Ru compound has structure of formula IId or IIe, ##STR00063## wherein R.sub.2 is alkyl (e.g., isopropyl).
38. The method of any one of claim 30-33, wherein Ru compound has structure of ##STR00064##
39. The method of any one of claim 30-33, wherein Ru compound has structure of ##STR00065##
Description
BRIEF DESCRIPTION OF THE FIGURES
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DETAILED DESCRIPTION
[0084] Certain embodiments of the invention provide a Ru catalyst and methods of making the catalyst described herein. In one embodiment, the invention can be prepared using silylium capped surfaces. For example, the first is a silylium capped sulfated zirconia. The second is a Lewis acid functionalized silica containing silylium (e.g., a silylium capped silica-aluminum alkoxide, also see Example 1). These silylium capped surfaces abstract halide ions from commercially available ruthenium catalysts (e.g., 2nd generation Grubbs-Hoveyda (GH-II) catalyst) to form ion-pairs. The cationic ruthenium catalysts are very active in olefin metathesis reactions. Data shown herein suggests that these cationic heterogeneous catalysts are at least twice as active as neutral homogeneous catalysts in solution. As described herein (e.g., see Example 1), the catalyst composition comprises supported cationic Ru catalyst via formation of ion-pairs. In certain embodiments, the catalyst composition does not comprise Ru catalyst that is bound to the support via covalent bond.
[0085] Accordingly, certain embodiments of the invention provide a catalyst composition, comprising a cationic Ruthenium (Ru) catalyst and a support. The cationic Ru catalyst has structure of Formula I:
##STR00003## [0086] wherein [0087] X is absent, halogen, O(O)CR.sub.t or OR.sub.x, wherein R.sub.t is alkyl or aryl and the alkyl, or aryl is optionally substituted with one or more substituent of hydroxy or halogen (e.g., F); wherein R.sub.x is alkyl, alkanoyl, or aryl, and the alkyl, alkanoyl, or aryl is optionally substituted with one or more substituent of hydroxy or halogen (e.g., F); wherein when X is O(O)CR.sub.t, the one or two oxygen(s) of O(O)CR.sub.t is bonded with the Ru; [0088] R.sub.1 (an alkylidene ligand for Ru) is aryl (e.g., indenylidene) or (CH)-aryl (e.g., benzylidene (CHPh)), wherein the aryl or (CH)-aryl is optionally substituted with one or more substituent selected from the group consisting of hydroxy, halogen, alkyl (e.g., C1-C6 alkyl), alkoxy (e.g., C1-C6 alkoxy), nitro (NO.sub.2), or aryl; and [0089] each L is independently O, alkoxy, P(R.sub.a).sub.3, heterocycle, or heteroaryl, one L may be absent, wherein the heterocycle, or heteroaryl is optionally substituted with one or more substituent selected from the group consisting of hydroxy, halogen, alkyl, adamantyl, alkoxy, nitro (NO.sub.2), or aryl that is optionally substituted with one or more alkyl, and wherein R.sub.a is alkyl, cycloalkyl, or aryl that is optionally substituted with one or more alkyl; wherein one L is absent when X is O(O)CR.sub.t and the two oxygen(s) of O(O)CR.sub.t are bonded with the Ru; [0090] wherein when X is absent, one L (a bidentate ligand when X is absent) is heterocycle, or heteroaryl substituted with one or more substituent (e.g., alkyl or adamantyl) and the substituent forms a RuC bond with the Ru; [0091] wherein Ru, together with the intervening carbon atoms of R.sub.1, and the oxygen atom of O or alkoxy of one L, optionally form a ring (e.g., a five-membered ring).
[0092] In certain embodiments, X is Cl, Br, or I.
[0093] In certain embodiments, X is Cl.
[0094] In certain embodiments, X is OR.sub.x, wherein R.sub.x is alkyl, alkanoyl, or aryl, and the alkyl, alkanoyl, or aryl is optionally substituted with one or more substituent of hydroxy or halogen (e.g., F). In certain embodiments, R.sub.x is alkanoyl (e.g., acetyl).
[0095] In certain embodiments, X is absent, and one L (a bidentate ligand when X is absent) is heterocycle, or heteroaryl substituted with one or more substituent (e.g., alkyl or adamantyl) and the substituent forms a RuC bond with the Ru.
[0096] In certain embodiments, X is O(O)CR.sub.t, wherein R.sub.t is alkyl or aryl and the alkyl, or aryl is optionally substituted with one or more substituent of hydroxy or halogen (e.g., F).
[0097] In certain embodiments, X is O(O)CR.sub.t, wherein one oxygen (i.e., the non-carbonyl oxygen) of the X forms a RuO bond with the Ru and the cationic Ru catalyst has structure of
##STR00004##
[0098] In certain embodiments, X is O(O)CR.sub.t, wherein the two oxygen atoms are bonded with the Ru and the cationic Ru catalyst has structure of
##STR00005##
[0099] In certain embodiments, X is halogen or OR.sub.x.
[0100] In certain embodiments, X is O(O)CR.sub.t or OR.sub.x.
[0101] In certain embodiments, R.sub.t is alkyl (e.g., C1-C6 alkyl, such as methyl or t-butyl). In certain embodiments, R.sub.t is aryl.
[0102] In certain embodiments, R.sub.1 is aryl or (CH)-aryl, wherein the aryl or (CH)-aryl is optionally substituted on the aryl ring with substituent Y, which is selected from the group consisting of hydroxy, halogen, alkyl, alkoxy, nitro (NO.sub.2), or aryl.
[0103] In certain embodiments, R.sub.1 is aryl optionally substituted with one or more substituent selected from the group consisting of hydroxy, halogen, alkyl, alkoxy, nitro (NO.sub.2), or aryl.
[0104] In certain embodiments, R.sub.1 is indenylidene.
[0105] In certain embodiments, R.sub.1 is indenylidene substituted with phenyl. In certain embodiments, R.sub.1 has structure of
##STR00006##
[0106] In certain embodiments, R.sub.1 is (CH)-aryl optionally substituted with one or more substituent selected from the group consisting of hydroxy, halogen, alkyl, alkoxy, nitro (NO.sub.2), or aryl.
[0107] In certain embodiments, R.sub.1 is benzylidene (CHPh), optionally substituted with one or more substituent selected from the group consisting of hydroxy, halogen, alkyl, alkoxy, nitro (NO.sub.2), or aryl.
[0108] In certain embodiments, R.sub.1 is benzylidene (CHPh).
[0109] In certain embodiments, R.sub.1 is p-nitrobenzylidene.
[0110] In certain embodiments, the cationic Ru catalyst has structure of Formula Ia:
##STR00007##
[0111] In certain embodiments, the cationic Ru catalyst has structure of Formula Ib:
##STR00008##
wherein R.sub.2 is alkyl (e.g., C1-C6 or C1-C4 alkyl, such as isopropyl). For example, in certain embodiments, the cationic Ru catalyst has structure of
##STR00009##
[0112] In certain embodiments, R.sub.2 is isopropyl.
[0113] In certain embodiments, the cationic Ruthenium catalyst has structure of
##STR00010##
[0114] In certain embodiments, the cationic Ru catalyst has structure of Formula Ic:
##STR00011##
[0115] In certain embodiments, one or two L is P(R.sub.a).sub.3, wherein R.sub.a is alkyl (e.g., C1-C6 alkyl), cycloalkyl (e.g., C4-C6 cycloalkyl), or aryl.
[0116] In certain embodiments, R.sub.a is cycloalkyl. In certain embodiments, P(R.sub.a).sub.3 is tricyclohexylphosphine (PCy.sub.3).
[0117] In certain embodiments, one or two L is P(R.sub.a).sub.3, wherein R.sub.a is alkyl, or aryl that is optionally substituted with one or more alkyl (e.g., C1-C6 alkyl). In certain embodiments, P(R.sub.a).sub.3 is trimethylphosphine, or tri-t-butylphosphine. In certain embodiments, P(R.sub.a).sub.3 is triphenylphosphine, or tri(o-tolyl)phosphine.
[0118] In certain embodiments, one or two L is optionally substituted heteroaryl. In certain embodiments, one or two L is pyridine.
[0119] In certain embodiments, one L is O or alkoxy (e.g., C1-C6 alkoxy), wherein the oxygen of O or alkoxy, together with the intervening carbon atoms of R.sub.1 (e.g., CHPh), and Ru form a ring (e.g., 5 membered ring). In certain embodiments, the alkoxy is O-isopropyl.
[0120] In certain embodiments, one or two L is optionally substituted heterocycle. In certain embodiments, one or two L is 2-imidazolidinyl. In certain embodiments, one or two L is 1,3-dimesityl-2-imidazolidinyl. In certain embodiments, one or two L is optionally substituted 2-pyrrolidinyl. In certain embodiments, one or two L is optionally substituted 5,5-dimethyl-2-pyrrolidinyl.
[0121] In certain embodiments, each L is independently selected from the group consisting of O, alkoxy, P(R.sub.a).sub.3,
##STR00012## [0122] wherein R.sub.b, R.sub.c, R.sub.d is independently H, alkyl, adamantyl, or aryl; and the aryl is optionally substituted with one or more alkyl. For example, in certain embodiments, one or two L is
##STR00013##
[0123] In certain embodiments, one or two L is
##STR00014##
[0124] In certain embodiments, R.sub.b and Re are the same group. In certain embodiments, R.sub.b and R.sub.c are each phenyl. In certain embodiments, R.sub.b and R.sub.c are each independently phenyl optionally substituted with one or more alkyl. In certain embodiments, R.sub.b and R.sup.e are each mesityl (Mes).
[0125] In certain embodiments, R.sub.b and R.sub.c are not the same group.
[0126] In certain embodiments, each L is independently O, alkoxy, P(R.sub.a).sub.3, or heterocycle.
[0127] In certain embodiments, each L is independently P(R.sub.a).sub.3, or heterocycle.
[0128] In certain embodiments, each L is independently O, alkoxy, or P(R.sub.a).sub.3.
[0129] In certain embodiments, each L is independently O, alkoxy, or heterocycle.
[0130] In certain embodiments, the cationic Ru catalyst has structure of Formula Id:
##STR00015## [0131] wherein R.sub.2 is alkyl (e.g., C1-C6 alkyl). In certain embodiments, R.sub.2 is isopropyl.
[0132] In certain embodiments, X is absent, and a substituent on one L (wherein L is heterocycle or heteroaryl) also forms a RuC bond. For example, in certain embodiments, one of R.sub.b and R.sub.c forms a RuC bond. Accordingly, in certain embodiments, the cationic Ru catalyst has structure of Formula Ie:
##STR00016## [0133] wherein R.sub.2 is alkyl (e.g., C1-C6 alkyl). In certain embodiments, R.sub.2 is isopropyl.
[0134] In certain embodiments, R.sub.c is adamantyl or alkyl. In certain embodiments, R.sub.c is adamantyl. In certain embodiments, R.sub.c is adamantyl and R.sub.b is optionally substituted aryl.
[0135] In certain embodiments, the cationic Ru catalyst has structure of
##STR00017##
[0136] Accordingly, in one embodiment, the invention provides the following exemplary cationic ruthenium catalysts that can be used in the methods of the invention. Thus, in certain embodiments, the cationic Ru catalyst has a structure of:
##STR00018##
[0137] In certain embodiments, the cationic Ru catalyst has structure of
##STR00019##
[0138] In certain embodiments, the cationic Ruthenium catalyst has structure of
##STR00020##
[0139] In certain embodiments, the cationic Ruthenium catalyst has structure of
##STR00021##
[0140] The support is an anionic solid support that provides negatively charged surface to support the cationic Ru catalyst. Accordingly, the cationic Ru catalyst could form ion-pairs with the anionic group on the support surface (e.g., anionic metal and/or non-metal oxide surface).
[0141] In certain embodiments, the support comprises metal and/or non-metal oxides. In certain embodiments, the support comprises SiO.sub.2/Al.sub.2O.sub.3.
[0142] In certain embodiments, the support comprises metal oxide (e.g., Al.sub.2O.sub.3, ZrO.sub.2, TiO.sub.2, or CeO.sub.2). In certain embodiments, the support comprises sulfated metal oxide, for example, sulfated zirconia (sulfated ZrO.sub.2), sulfated TiO.sub.2, or sulfated CeO.sub.2.
[0143] In certain embodiments, the support comprises non-metal oxide, for example, silica (SiO.sub.2). In certain embodiments, the support comprises oxide E.sub.xO.sub.y, wherein E is metal or non-metal; x is 1 or 2; and y is 2 or 3. For example, in certain embodiments, the support comprises oxide E.sub.xO.sub.y, wherein E is Si, Al, Zr, Ti, or Ce; x is 1 or 2; and y is 2 or 3. The oxide E.sub.xO.sub.y surface may comprise-OH group. In certain embodiments, the support comprises oxide-Aluminum alkoxide (E.sub.xO.sub.y/Al(OR.sup.s).sub.3) having structure of
##STR00022##
[0144] wherein R.sup.s is alkyl (e.g., C1-C6 or C1-C4 alkyl such as t-butyl) optionally substituted with one or more halogen (e.g., F).
[0145] In certain embodiments, the support comprises silica-Aluminum alkoxide (SiO.sub.2/Al(OR.sup.s).sub.3), wherein R.sup.s is alkyl (e.g., C1-C6 or C1-C4 alkyl such as t-butyl) optionally substituted with one or more halogen (e.g., F).
[0146] In certain embodiments, R.sup.s is perfluoro alkyl (e.g., perfluoro t-butyl). In certain embodiments, R.sup.s is C(CF.sub.3).sub.3.
[0147] In certain embodiments, the silica-Aluminum alkoxide (SiO.sub.2/Al(OR.sup.s).sub.3) has structure of
##STR00023##
[0148] In certain embodiments, the catalyst composition comprises ion-pair of a cationic Ru catalyst described herein (e.g., Formula I, Ia, Ib, Ic, or Id), and an anionic support described herein (e.g., sulfated zirconium oxide (SZO), or silica-aluminum alkoxide). For example, in certain embodiments, the catalyst composition comprises ion-pair having structure of
##STR00024## [0149] wherein R.sup.s is alkyl (e.g., C1-C6 or C1-C4 alkyl such as t-butyl) optionally substituted with one or more halogen (e.g., F).
[0150] In certain embodiments, the catalyst composition comprises ion-pair having structure of
##STR00025##
[0151] In certain embodiments, the catalyst composition comprises ion-pair [(IMes)Ru(CH (o-O.sup.iPrC.sub.6H.sub.4)Cl][(R.sup.sO).sub.3AlOSi)] (1) (also see Example 1 and
[0152] In certain embodiments, the catalyst composition comprises a mole percentage of the cationic Ru catalyst at about 0.001 to 1 mol %, 0.005 to 1 mol %, 0.01 to 1 mol %, 0.05 to 1 mol %, 0.1 to 1 mol %, 0.5 to 1 mol %, or 1 mol % to 5 mol %. In certain embodiments, the catalyst composition comprises a mole percentage of the cationic Ru catalyst at about 5, 1, 0.5, 0.1, 0.05, 0.01, 0.005, 0.001 mol % or lower. In certain embodiments, the catalyst composition comprises a mole percentage of the cationic Ru catalyst at about 0.001, 0.005, 0.01, 0.05, 0.1, 0.5, 1, 5 mol % or higher.
Methods
[0153] Certain embodiments of the invention provide a method of catalyzing olefin metathesis, comprising contacting one or more reactant olefins with a catalyst composition described herein.
[0154] Olefin metathesis reactions are described herein and known in the art. Olefin metathesis reaction may occur between two substrates which are not joined by a bond (e.g., intermolecular metathesis reaction) or between two portions of a single substrate (e.g., intramolecular metathesis reaction). In certain embodiments, the reaction is cross-metathesis. In some embodiments, the reaction is an ethenolysis reaction. In certain embodiments, the reaction is ring-closing metathesis. In certain embodiments, the reaction is ring-closing metathesis, ring-opening metathesis, or cross-metathesis. In certain embodiments, the reaction is ring-closing metathesis, ring-opening metathesis, or acyclic diene metathesis.
[0155] In certain embodiments, the method comprises contacting two olefins with a catalyst composition described herein. For example, the methods couples two olefins to form a product olefin. In certain embodiments, the two olefins are the same olefin (e.g., two 1-decene molecules are coupled to produce 9-octadecene). In certain embodiments, the two olefins are different olefins (i.e., a first reactant compound and a second reactant compound), for example, the method couples allylbenzene and 1,4-diacetoxybutene.
[0156] The terms olefin and alkene as used herein refer to a compound comprising one or more CC bond(s). In certain embodiments, the olefin has one CC bond. In certain embodiments, the olefin has two CC bonds.
[0157] In certain embodiments, each olefin reactant compound is independently an unsaturated, branched or unbranched, C2-C26 hydrocarbon chain, wherein one or more carbon of the hydrocarbon chain is optionally replaced with O, N(R.sub.g), S, Si(R.sub.h).sub.2, cycloalkyl, aryl, or heteroaryl, and wherein the hydrocarbon chain is optionally substituted on carbon with one or more substituents selected from the group consisting of alkoxy, alkanoyl, alkanoyloxy, alkoxycarbonyl, halo, hydroxy, amino, mercapto, oxo (O), and thioxo (=S), wherein R.sub.g and R.sub.h are each independently H or alkyl (e.g., C.sub.1-C.sub.6).
[0158] In certain embodiments, the olefin reactant compound is a straight chain, branched or unbranched, or cyclic olefin compound of 2 to 20 carbon atoms comprising one or more double bond, and the olefin compound is optionally substituted with one or more substituents selected from the group consisting of halo, hydroxy, amino, mercapto, oxo (O), thioxo (=S), aryl, and heteroaryl.
[0159] In certain embodiments, an olefin reactant compound is a cyclic alkene (cycloalkene).
[0160] In certain embodiments, an olefin reactant compound is a C.sub.2-C.sub.26 olefin compound. In certain embodiments, an olefin reactant compound is a C.sub.2-C.sub.24 olefin compound. In certain embodiments, an olefin reactant compound is a C.sub.2-C.sub.22 olefin compound. In certain embodiments, an olefin reactant compound is a C.sub.2-C.sub.20 olefin compound. In certain embodiments, an olefin reactant compound is a C.sub.2-C.sub.18 olefin compound. In certain embodiments, an olefin reactant compound is a C.sub.2-C.sub.16 olefin compound. In certain embodiments, an olefin reactant compound is a C.sub.2-C.sub.14 olefin compound. In certain embodiments, an olefin reactant compound is a C.sub.2-C.sub.12 olefin compound. In certain embodiments, an olefin reactant compound is a C.sub.2-C.sub.10 olefin compound. In certain embodiments, an olefin reactant compound is a C.sub.2-C.sub.8 olefin compound. In certain embodiments, an olefin reactant compound is a C.sub.2-C.sub.6 olefin compound. In certain embodiments, an olefin reactant compound is a C.sub.2-C.sub.4 olefin compound. In certain embodiments, an olefin reactant compound is optionally substituted with one or more substituents selected from the group consisting of halo, hydroxy, amino, mercapto, oxo (O), thioxo (S), alkoxy, aryl, and heteroaryl.
[0161] In certain embodiments, an olefin reactant compound is a terminal olefin (e.g., C.sub.2-C.sub.26 olefin compound), such as 1-decene or 1-octene.
[0162] In certain embodiments, an olefin reactant compound is not a terminal olefin.
[0163] In certain embodiments, an olefin reactant compound is methyl acrylate.
[0164] In certain embodiments, an olefin reactant compound is ethyl oleate.
[0165] In certain embodiments, an olefin reactant compound is allylbenzene.
[0166] In certain embodiments, an olefin reactant compound is 1,4-diacetoxybutene.
[0167] In certain embodiments, an olefin reactant compound is allyltrimethylsilane.
[0168] In certain embodiments, an olefin reactant compound is 2,2-dimethyallylmalonate.
[0169] In certain embodiments, the contacting comprises contacting at about 15-30 C., 16-29 C., 17-28 C., 18-27 C., 19-26 C., or 20-25 C.
[0170] In certain embodiments, the method is conducted for at least 5, 10, 15, 30, 45 minutes, 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h, 10 h, 12 h, 14 h, 16 h, 18 h, 20 h, 22 h, 24 h, 36 h, 48 h, 72 h or longer.
[0171] In certain embodiments, the method is conducted at about 1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000, 10000, 100000, 1000000 or higher equivalents of reactant olefin per Ru. In certain embodiments, the method is conducted at about 1000 to 1000000, 2000 to 100000, 3000 to 10000, 1000 to 100000 or 1000 to 10000 equivalents of reactant olefin per Ru.
[0172] In certain embodiments, the method has a TON (TON=turnover number at max conversion=[mol product][mol Ru]) of at least 100, 500, 1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000, 10000, 20000, 30000, 40000, 50000, or higher.
[0173] In certain embodiments, the method has a TOF (TOF=initial turnover frequency (per minute)=[mol product]/[mol Ru][time]) of at least 10, 50, 100, 150, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1500, 2000, 2500, 3000, or higher.
[0174] Certain embodiments of the invention provide a method of making a catalyst composition described herein, comprising contacting a Ru compound of Formula II with a silylium on a support. For example, after contacting, the Ru compound of Formula II becomes a supported cationic Ru catalyst described herein, and silyl halide (e.g., .sup.iPr.sub.3SiCl) is formed.
[0175] In certain embodiments, the silylium has structure of .sup.+Si(R.sub.m).sub.3, wherein R.sub.m is alkyl or aryl, and the aryl is optionally substituted with one or more alkyl.
[0176] In certain embodiments, R.sub.m is alkyl (e.g., C1-C6, or C1-C4 alkyl). In certain embodiments, R.sub.m is isopropyl.
[0177] In certain embodiments, R.sub.m is aryl (e.g., phenyl) optionally substituted with one or more alkyl.
[0178] The support is an anionic solid support that provides negatively charged surface to support the silylium. Accordingly, the silylium could form ion-pairs with the anionic group on the support surface.
[0179] In certain embodiments, the support comprises metal and/or non-metal oxides. In certain embodiments, the support comprises SiO.sub.2/Al.sub.2O.sub.3.
[0180] In certain embodiments, the support comprises metal oxide (e.g., Al.sub.2O.sub.3, ZrO.sub.2, TiO.sub.2, or CeO.sub.2). In certain embodiments, the support comprises sulfated metal oxide, for example, sulfated zirconia (sulfated ZrO.sub.2), sulfated TiO.sub.2, or sulfated CeO.sub.2.
[0181] In certain embodiments, the support comprises non-metal oxide, for example, silica (SiO.sub.2).
[0182] In certain embodiments, the support comprises oxide E.sub.xO.sub.y, wherein E is metal or non-metal; x is 1 or 2; and y is 2 or 3. For example, in certain embodiments, the support comprises oxide E.sub.xO.sub.y, wherein E is Si, Al, Zr, Ti, or Ce; x is 1 or 2; and y is 2 or 3. In certain embodiments, the oxide E.sub.xO.sub.y surface may comprise-OH group. In certain embodiments, the support comprises oxide-Aluminum alkoxide (E.sub.xO.sub.y/Al(OR.sup.s).sub.3) having structure of
##STR00026## [0183] wherein R.sup.s is alkyl (e.g., C1-C6 or C1-C4 alkyl such as t-butyl) optionally substituted with one or more halogen (e.g., F).
[0184] In certain embodiments, the support comprises silica-aluminum alkoxide (SiO.sub.2/Al(OR.sup.s).sub.3), wherein R.sup.s is alkyl (e.g., C1-C6 or C1-C4 alkyl such as t-butyl) optionally substituted with one or more halogen (e.g., F). In certain embodiments, R.sup.s is perfluoro alkyl (e.g., perfluoro t-butyl). In certain embodiments, R.sup.s is C(CF.sub.3).sub.3.
[0185] In certain embodiments, the silica-aluminum alkoxide (SiO.sub.2/Al(OR.sup.s).sub.3) has structure of
##STR00027##
[0186] In certain embodiments, the silynium on a support has structure of
##STR00028## [0187] wherein alkyl (e.g., C1-C6 or C1-C4 alkyl such as t-butyl) substituted with one or more halogen (e.g., F). In certain embodiments, R.sup.s is C(CF.sub.3).sub.3.
[0188] The Ru compound to be contacted with the supported silylium has structure of Formula II:
##STR00029## [0189] wherein [0190] each X is independently halogen, O(O)CR.sub.t or OR.sub.x, one X may be absent, wherein R.sub.t is alkyl or aryl and the alkyl, or aryl is optionally substituted with one or more substituent of hydroxy or halogen (e.g., F); wherein R.sub.x is alkyl, alkanoyl, or aryl, and the alkyl, alkanoyl, or aryl is optionally substituted with one or more substituent of hydroxy or halogen (e.g., F); wherein when X is O(O)CR.sub.t, the one oxygen of O(O)CR.sub.t is bonded with the Ru, or only one X is O(O)CR.sub.t wherein the two oxygens of O(O)CR.sub.t are bonded with the Ru; [0191] R.sub.1 is aryl (e.g., indenylidene) or (CH)-aryl (e.g., benzylidene), wherein the aryl or (CH)-aryl is optionally substituted with one or more substituent selected from the group consisting of hydroxy, halogen, alkyl, alkoxy, nitro (NO.sub.2), or aryl; and [0192] each L is independently O, alkoxy, P(R.sub.a).sub.3, heterocycle, or heteroaryl, one L may be absent, wherein the heterocycle, or heteroaryl is optionally substituted with one or more substituent selected from the group consisting of hydroxy, halogen, alkyl, adamantyl, alkoxy, nitro (NO.sub.2), or aryl that is optionally substituted with one or more alkyl (e.g., mesityl), and wherein R.sub.a is alkyl, cycloalkyl, or aryl that is optionally substituted with one or more alkyl; wherein one L is absent when only one X is O(O)CR.sub.t and the two oxygen(s) of O(O)CR.sub.t are bonded with the Ru; [0193] wherein when one X is absent, one L (a bidentate ligand when X is absent) is heterocycle, or heteroaryl substituted with one or more substituent (e.g., alkyl or adamantyl) and the substituent forms a RuC bond with the Ru; [0194] wherein Ru, together with the intervening carbon atoms of R.sub.1, and the oxygen atom of O or alkoxy of one L, optionally form a ring (e.g., a five-membered ring).
[0195] In certain embodiments, one or two X is halogen.
[0196] In certain embodiments, one or two X is OR.sub.x, wherein R.sub.x is alkyl, alkanoyl, or aryl, and the alkyl, alkanoyl, or aryl is optionally substituted with one or more substituent of hydroxy or halogen (e.g., F). In certain embodiments, R.sub.x is alkanoyl (e.g., acetyl).
[0197] In certain embodiments, one X is absent, and one L (a bidentate ligand when X is absent) is heterocycle, or heteroaryl substituted with one or more substituent (e.g., alkyl or adamantyl) and the substituent forms a RuC bond with the Ru.
[0198] In certain embodiments, one X is O(O)CR.sub.t, wherein R.sub.t is alkyl or aryl and the alkyl, or aryl is optionally substituted with one or more substituent of hydroxy or halogen (e.g., F).
[0199] In certain embodiments, each X is O(O)CR.sub.t, wherein one oxygen of X forms a RuO bond with the Ru and the Ru of formula II has structure of
##STR00030##
[0200] In certain embodiments, the Ru compound has structure of formula IIa,
##STR00031##
[0201] In certain embodiments, the Ru compound has structure of formula IIb,
##STR00032## [0202] wherein R.sub.2 is alkyl (e.g., C1-C6 alkyl such as isopropyl).
[0203] In certain embodiments, the Ru compound has structure of formula IIc,
##STR00033##
[0204] In certain embodiments, one or two L is P(R.sub.a).sub.3, wherein R.sub.a is alkyl, cycloalkyl, or aryl.
[0205] In certain embodiments, R.sub.a is cycloalkyl. In certain embodiments, P(R.sub.a).sub.3 is tricyclohexylphosphine (PCy.sub.3).
[0206] In certain embodiments, one or two L is P(R.sub.a).sub.3, wherein R.sub.a is alkyl, or aryl that is optionally substituted with one or more alkyl. In certain embodiments, P(R.sub.a).sub.3 is trimethylphosphine, or tri-t-butylphosphine. In certain embodiments, P(R.sub.a).sub.3 is triphenylphosphine, or tri(o-tolyl)phosphine.
[0207] In certain embodiments, one or two L is optionally substituted heteroaryl. In certain embodiments, one or two L is pyridine.
[0208] In certain embodiments, one L is O or alkoxy, wherein the oxygen of O or alkoxy, together with the intervening carbon atoms of R.sub.1 (e.g., =CHPh), and Ru form a ring (e.g., 5 membered ring). In certain embodiments, the alkoxy is O-isopropyl.
[0209] In certain embodiments, one or two L is optionally substituted heterocycloalkyl. In certain embodiments, one or two L is 2-imidazolidinyl. In certain embodiments, one or two L is 1,3-dimesityl-2-imidazolidinyl. In certain embodiments, one or two L is optionally substituted 2-pyrrolidinyl. In certain embodiments, one or two L is optionally substituted 5,5-dimethyl-2-pyrrolidinyl.
[0210] In certain embodiments, each L is independently selected from the group consisting of O, alkoxy, P(R.sub.a).sub.3,
##STR00034## [0211] wherein R.sub.b, R.sub.c, R.sub.d is independently H, alkyl, adamantyl, or aryl; and the aryl is optionally substituted with one or more alkyl. For example, in certain embodiments, one or two L is
##STR00035##
[0212] In certain embodiments, one or two L is
##STR00036##
[0213] In certain embodiments, R.sub.b and R.sub.c are the same group. In certain embodiments, R.sub.b and R.sub.c are each phenyl. In certain embodiments, R.sub.b and R.sub.c are each independently phenyl optionally substituted with one or more alkyl. In certain embodiments, R.sub.b and R.sub.c are each mesityl (Mes).
[0214] In certain embodiments, R.sub.b and R.sub.c are not the same group.
[0215] In certain embodiments, each L is independently O, alkoxy, P(R.sub.a).sub.3, or heterocycle.
[0216] In certain embodiments, each L is independently P(R.sub.a).sub.3, or heterocycle.
[0217] In certain embodiments, each L is independently O, alkoxy, or P(R.sub.a).sub.3.
[0218] In certain embodiments, each L is independently O, alkoxy, or heterocycle.
[0219] In certain embodiments, the Ru compound has structure of formula IId,
##STR00037## [0220] wherein R.sub.2 is alkyl (e.g., isopropyl).
[0221] In certain embodiments, only one X is absent, and a substituent on one L (wherein L is heterocycle or heteroaryl) also forms a RuC bond. For example, in certain embodiments, one of R.sub.b and R.sub.c forms a RuC bond with the Ru. Accordingly, in certain embodiments, the cationic Ru catalyst has structure of Formula Ile:
##STR00038## [0222] wherein R.sub.2 is alkyl (e.g., C1-C6 alkyl). In certain embodiments, R.sub.2 is isopropyl.
[0223] In certain embodiments, R.sub.c is adamantyl or alkyl. In certain embodiments, R.sub.c is adamantyl. In certain embodiments, R.sub.c is adamantyl and R.sub.b is optionally substituted aryl.
[0224] In certain embodiments, R.sub.1 is aryl (e.g., indenylidene) or (CH)-aryl (e.g., benzylidene), wherein the aryl or (CH)-aryl is optionally substituted with substituent Y, which is selected from the group consisting of hydroxy, halogen, alkyl, alkoxy, nitro (NO.sub.2), or aryl.
[0225] Accordingly, in one embodiment, the following exemplary ruthenium catalysts can be used to prepare cationic ruthenium catalysts of the invention. Thus, in certain embodiments, the Ru compound of formula II has structure of
##STR00039##
[0226] In certain embodiments, the Ru compound of formula II has structure of
##STR00040##
[0227] In certain embodiments, the the Ru compound of formula II has structure of
##STR00041##
[0228] In certain embodiments, the the Ru compound of formula II has structure of
##STR00042##
[0229] In certain embodiments, the contacting comprises mixing a Ru compound of Formula II with a silylium on a support in a non-polar organic solvent (e.g., an alkane such as pentane). In certain embodiments, the contacting comprises contacting (e.g., mixing) at about-40 C., 30 C., 20 C., 10 C., 0 C., 10 C., 20 C., 30 C., 40 C., 50 C., 60 C., 70 C., or 80 C. In certain embodiments, the contacting comprises contacting (e.g., mixing) at about 40-80 C., 30-70 C., 20-60 C., 10-50 C., 0-40 C. or 10-30 C. In certain embodiments, the contacting comprises contacting (e.g., mixing) at about 15-30 C., 16-29 C., 17-28 C., 18-27 C., 19-26 C., or 20-25 C.
[0230] In certain embodiments, the contacting (e.g., mixing) is conducted for a duration of about 1 minute to 72 hrs, 5 min to 48 hrs, 10 min to 24 hrs, 15 min to 12 hrs, 20 min to 6 hrs, 25 min to 3 hrs, 30 min to 1 hour. In certain embodiments, the method is conducted for at least 5, 10, 15, 30, 45 minutes, 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h, 10 h, 12 h, 14 h, 16 h, 18 h, 20 h, 22 h, 24 h, 36 h, 48 h, 72 h or longer.
[0231] In certain embodiments, contacting (e.g., mixing) is conducted at about 220 C. to 80 C. (e.g., about 196 C.) followed by mixing at about 15-30 C., 16-29 C., 17-28 C., 18-27 C., 19-26 C., or 20-25 C.
[0232] In certain embodiments, the method of making a catalyst composition described herein further comprises separating the solid with the non-polar organic solvent (e.g., filtering).
[0233] In certain embodiments, the method of making a catalyst composition described herein further comprises drying the product solid under vacuum.
Certain Definitions
[0234] The following definitions are used, unless otherwise described: halo or halogen is fluoro, chloro, bromo, or iodo. Alkyl, alkoxy, etc. denote both straight and branched groups; but reference to an individual radical such as propyl embraces only the straight chain radical, a branched chain isomer such as isopropyl being specifically referred to.
[0235] The term alkyl, by itself or as part of another substituent, means, unless otherwise stated, a straight or branched chain hydrocarbon radical, having the number of carbon atoms designated (i.e., C.sub.1-8 means one to eight carbons). Examples include (C.sub.1-C.sub.8)alkyl, (C.sub.2-C.sub.8)alkyl, (C.sub.1-C.sub.6)alkyl, (C.sub.2-C.sub.6)alkyl, (C.sub.1-C.sub.3)alkyl, and (C.sub.3-C.sub.6)alkyl. Examples of alkyl groups include methyl, ethyl, n-propyl, iso-propyl, n-butyl, t-butyl, iso-butyl, sec-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, and higher homologs and isomers. (C.sub.1-C.sub.6)alkyl can be methyl, ethyl, propyl, isopropyl, butyl, iso-butyl, sec-butyl, pentyl, 3-pentyl, or hexyl.
[0236] The term alkoxy refers to an alkyl groups attached to the remainder of the molecule via an oxygen atom (oxy). For example, (C.sub.1-C.sub.6)alkoxy can be methoxy, ethoxy, propoxy, isopropoxy, butoxy, iso-butoxy, sec-butoxy, pentoxy, 3-pentoxy, or hexyloxy.
[0237] The term halo or halogen refers to bromo, chloro, fluoro or iodo. In some embodiments, halogen refers to chloro or fluoro. In some embodiments, halogen refers to fluoro.
[0238] The term cycloalkyl refers to a saturated or partially unsaturated (non-aromatic) all carbon ring having 3 to 8 carbon atoms (i.e., (C.sub.3-C.sub.8)carbocycle). The term also includes multiple condensed, saturated all carbon ring systems (e.g., ring systems comprising 2, 3 or 4 carbocyclic rings). Accordingly, carbocycle includes multicyclic carbocyles such as a bicyclic carbocycles (e.g., bicyclic carbocycles having about 3 to 15 carbon atoms, about 6 to 15 carbon atoms, or 6 to 12 carbon atoms such as bicyclo[3.1.0]hexane and bicyclo[2.1.1]hexane), and polycyclic carbocycles (e.g tricyclic and tetracyclic carbocycles with up to about 20 carbon atoms). The rings of the multiple condensed ring system can be connected to each other via fused, spiro and bridged bonds when allowed by valency requirements. For example, multicyclic carbocyles can be connected to each other via a single carbon atom to form a spiro connection (e.g., spiropentane, spiro[4,5]decane, etc), via two adjacent carbon atoms to form a fused connection (e.g., carbocycles such as decahydronaphthalene, norsabinane, norcarane) or via two non-adjacent carbon atoms to form a bridged connection (e.g., norbornane, bicyclo[2.2.2]octane, etc). Non-limiting examples of cycloalkyls include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, bicyclo[2.2.1]heptane, pinane, and adamantane. (C.sub.3-C.sub.6) cycloalkyl can be cyclopropyl, cyclobutyl, cyclopentyl, or cyclohexyl.
[0239] The term aryl as used herein refers to a single all carbon aromatic ring or a multiple condensed all carbon ring system wherein at least one of the rings is aromatic. For example, in certain embodiments, an aryl group has 6 to 20 carbon atoms, 6 to 14 carbon atoms, 6 to 12 carbon atoms, or 6 to 10 carbon atoms. Aryl includes a phenyl radical. Aryl also includes multiple condensed carbon ring systems (e.g., ring systems comprising 2, 3 or 4 rings) having about 9 to 20 carbon atoms in which at least one ring is aromatic and wherein the other rings may be aromatic or not aromatic (i.e., cycloalkyl. The rings of the multiple condensed ring system can be connected to each other via fused, spiro and bridged bonds when allowed by valency requirements. It is to be understood that the point of attachment of a multiple condensed ring system, as defined above, can be at any position of the ring system including an aromatic or a carbocycle portion of the ring. Non-limiting examples of aryl groups include, but are not limited to, phenyl, indenyl, indanyl, naphthyl, 1, 2, 3, 4-tetrahydronaphthyl, anthracenyl, and the like.
[0240] The term heterocycle refers to a single saturated or partially unsaturated ring that has at least one atom other than carbon in the ring, wherein the atom is selected from the group consisting of oxygen, nitrogen and sulfur; the term also includes multiple condensed ring systems that have at least one such saturated or partially unsaturated ring, which multiple condensed ring systems are further described below. Thus, the term includes single saturated or partially unsaturated rings (e.g., 3, 4, 5, 6 or 7-membered rings) from about 1 to 6 carbon atoms and from about 1 to 3 heteroatoms selected from the group consisting of oxygen, nitrogen and sulfur in the ring. The sulfur and nitrogen atoms may also be present in their oxidized forms. Exemplary heterocycles include but are not limited to azetidinyl, tetrahydrofuranyl and piperidinyl. The term heterocycle also includes multiple condensed ring systems (e.g., ring systems comprising 2, 3 or 4 rings) wherein a single heterocycle ring (as defined above) can be condensed with one or more groups selected from cycloalkyl, aryl, and heterocycle to form the multiple condensed ring system. The rings of the multiple condensed ring system can be connected to each other via fused, spiro and bridged bonds when allowed by valency requirements. It is to be understood that the individual rings of the multiple condensed ring system may be connected in any order relative to one another. It is also to be understood that the point of attachment of a multiple condensed ring system (as defined above for a heterocycle) can be at any position of the multiple condensed ring system including a heterocycle, aryl and carbocycle portion of the ring. In one embodiment the term heterocycle includes a 3-15 membered heterocycle. In one embodiment the term heterocycle includes a 3-10 membered heterocycle. In one embodiment the term heterocycle includes a 3-8 membered heterocycle. In one embodiment the term heterocycle includes a 3-7 membered heterocycle. In one embodiment the term heterocycle includes a 3-6 membered heterocycle. In one embodiment the term heterocycle includes a 4-6 membered heterocycle. In one embodiment the term heterocycle includes a 3-10 membered monocyclic or bicyclic heterocycle comprising 1 to 4 heteroatoms. In one embodiment the term heterocycle includes a 3-8 membered monocyclic or bicyclic heterocycle heterocycle comprising 1 to 3 heteroatoms. In one embodiment the term heterocycle includes a 3-6 membered monocyclic heterocycle comprising 1 to 2 heteroatoms. In one embodiment the term heterocycle includes a 4-6 membered monocyclic heterocycle comprising 1 to 2 heteroatoms. Exemplary heterocycles include, but are not limited to aziridinyl, azetidinyl, pyrrolidinyl, piperidinyl, homopiperidinyl, morpholinyl, thiomorpholinyl, piperazinyl, tetrahydrofuranyl, dihydrooxazolyl, tetrahydropyranyl, tetrahydrothiopyranyl, 1,2,3,4-tetrahydroquinolyl, benzoxazinyl, dihydrooxazolyl, chromanyl, 1,2-dihydropyridinyl, 2,3-dihydrobenzofuranyl, 1,3-benzodioxolyl, 1,4-benzodioxanyl, spiro[cyclopropane-1,1-isoindolinyl]-3-one, isoindolinyl-1-one, 2-oxa-6-azaspiro[3.3]heptanyl, imidazolidin-2-one imidazolidine, pyrazolidine, butyrolactam, valerolactam, imidazolidinone, hydantoin, dioxolane, phthalimide, 1,4-dioxane, 2-imidazolidinyl, 1,3-dimesityl-2-imidazolidinyl, and 5,5-dimethyl-2-pyrrolidinyl.
[0241] The term heteroaryl as used herein refers to a single aromatic ring that has at least one atom other than carbon in the ring, wherein the atom is selected from the group consisting of oxygen, nitrogen and sulfur; heteroaryl also includes multiple condensed ring systems that have at least one such aromatic ring, which multiple condensed ring systems are further described below. Thus, heteroaryl includes single aromatic rings of from about 1 to 6 carbon atoms and about 1-4 heteroatoms selected from the group consisting of oxygen, nitrogen and sulfur. The sulfur and nitrogen atoms may also be present in an oxidized form provided the ring is aromatic. Exemplary heteroaryl ring systems include but are not limited to pyridyl, pyrimidinyl, oxazolyl or furyl. Heteroaryl also includes multiple condensed ring systems (e.g., ring systems comprising 2, 3 or 4 rings) wherein a heteroaryl group, as defined above, is condensed with one or more rings selected from cycloalkyl, aryl, heterocycle, and heteroaryl. It is to be understood that the point of attachment for a heteroaryl or heteroaryl multiple condensed ring system can be at any suitable atom of the heteroaryl or heteroaryl multiple condensed ring system including a carbon atom and a heteroatom (e.g., a nitrogen). Exemplary heteroaryls include but are not limited to pyridyl, pyrrolyl, pyrazinyl, pyrimidinyl, pyridazinyl, pyrazolyl, thienyl, indolyl, imidazolyl, triazolyl, tetrazolyl, oxazolyl, isoxazolyl, thiazolyl, furyl, oxadiazolyl, thiadiazolyl, quinolyl, isoquinolyl, benzothiazolyl, benzoxazolyl, indazolyl, quinoxalyl, and quinazolyl.
[0242] As used herein, the term heteroatom is meant to include oxygen (O), nitrogen (N), sulfur(S) and silicon (Si).
[0243] As used herein a wavy line that intersects a bond in a chemical structure indicates the point of attachment of the bond that the wavy bond intersects in the chemical structure to the remainder of a molecule.
[0244] When a bond in a compound formula herein is drawn in a non-stereochemical manner (e.g. flat), the atom to which the bond is attached includes all stereochemical possibilities. When a bond in a compound formula herein is drawn in a defined stereochemical manner (e.g. bold, bold-wedge, dashed or dashed-wedge), it is to be understood that the atom to which the stereochemical bond is attached is enriched in the relative stereoisomer depicted unless otherwise noted. In one embodiment, the compound may be at least 51% the relative stereoisomer depicted. In another embodiment, the compound may be at least 60% the relative stereoisomer depicted. In another embodiment, the compound may be at least 80% the relative stereoisomer depicted. In another embodiment, the compound may be at least 90% the relative stereoisomer depicted. In another embodiment, the compound may be at least 95% the relative stereoisomer depicted. In another embodiment, the compound may be at least 99% the relative stereoisomer depicted.
[0245] Certain embodiments of the invention will be illustrated in the following non-limiting Example.
Example 1 Ruthenium Catalysts for Olefin Metathesis
[0246] The incorporation of organometallic groups onto oxide surfaces is a strategy to access more efficient and selective heterogeneous catalysts..sup.1 One of the success stories in this area is the development of well-defined heterogeneous catalysts for olefin metathesis,
[0247] The reaction shown in
[0248] We recently described oxides capped with silylium-like ions..sup.8 Silylium-like ions (R.sub.3Si.sup.+) are very strong Lewis acids.sup.9 that abstract halides from transition metal, lanthanide, or actinide complexes to form R.sub.3SiX (X=halide) and an ion-pair..sup.10 Oxides capped with silylium-like ions behave similarly,.sup.11 which provides a complementary methodology to the common protonolysis route typified in
Synthesis and Characterization
##STR00043##
[0249] Synthesis of 1: [.sup.iPr.sub.3Si][SiOAl(OR.sup.F).sub.3] (2 g, 0.48 mmol=SiOHAl(OR.sup.F).sub.3) and Grubbs-Hoveyda Second Generation Catalyst (0.313 g, 0.50 mmol) were loaded into a teflon-valved flask containing two arms separated by a medium porosity frit (double Schlenk) and evacuated under diffusion pump vacuum. Pentane (10 mL) was transferred to the flask at 196 C. The slurry was warmed up to room temperature and stirred for 30 minutes. The green solution was filtered to the other side of the double Schlenk. The remaining solid was washed by condensing solvent from the other arm of the double Schlenk at 196 C., warming to room temperature, stirring for 2 minutes, and filtering the solvent back to the other side of the flask. This was repeated until the solution remained colorless upon stirring, then filtered a final time. The solid was dried under diffusion pump vacuum for 1 hour. The brown material was stored in a glovebox freezer at 20 C. Elemental analysis: 2.2% Ru.
[0250] Methods to prepare a silylium on a support are described herein and known in art, for example, in D Culver, et al., Chem. Sci., 2020, 11, 1510-1517 (DOI: 10.1039/C9SC05904K) and D Culver, et al., Angew Chem Int Ed Engl. 2018 Nov. 5; 57 (45): 14902-14905 (doi: 10.1002/anie.201809199), the entire contents of which are incorporated by reference herein.
NMR Spectroscopy
[0251] Solution NMR spectra at 7.05 T were acquired on an Avance Bruker 300. .sup.1H NMR spectra were referenced to the natural abundance residual solvent peak. Solid state NMR spectra at UC Riverside were recorded in 4 mm zirconia rotors at 8-12 KHz spinning at the magic angle at 14.1 T on an Avance Bruker NEO600 spectrometer equipped with a standard-bore magnet.
Quantification of Triisopropylsilyl Chloride
[0252] In a sealed J-young NMR tube, [.sup.iPr.sub.3Si][SiOAl(OR.sup.F).sub.3] (50 mg, 0.012 mmol SiOHAl(OR.sup.F).sub.3), Grubbs-Hoveyda Second Generation Catalyst (10 mg, 0.016 mmol), and hexamethyl benzene were slurred in C.sub.6D.sub.6. The reaction was periodically shaken over a period of 30 minutes, before collecting an NMR spectrum. Hexamethyl benzene serves as an internal standard to quantitate the amount of triisopropylsilyl chloride (TIPSCl) that comes off during the reaction (
TABLE-US-00001 TABLE 1 Quantification of TIPSCl. A B C [.sup.iPr.sub.3Si][SiOAl(OR.sup.F).sub.3] 33.1 33.9 57.5 (mg) ISTD (mg) 11.1 8.3 1.2 TIPSCl (mg) 6.1 6.5 1.1 mmol/g Ru 0.17 0.18 0.18
Quantification of GH2
[0253] In a sealed J-young NMR tube, 1 (50 mg, 0.009 mmol Ru), tetrabutylammonium chloride (2.5 mg, 0.009 mmol), and hexamethyl benzene were slurred in C.sub.6D.sub.6. The reaction was sonicated over a period of 30 minutes, before collecting an NMR spectrum. Hexamethyl benzene serves as an internal standard to quantitate the amount of Ru that comes off during the reaction (
TABLE-US-00002 TABLE 2 Quantification of GH2. A 1 (mg) 40.0 ISTD (mg) 4.5 GH2 (mg) 11.2 mmol/g Ru 0.18
Quantification of GH2
[0254] In a sealed J-young NMR tube, 1 (50 mg, 0.009 mmol Ru), ammonium chloride (0.5 mg, 0.009 mmol), and hexamethyl benzene were slurred in C.sub.6D.sub.6. The reaction was sonicated over a period of 30 minutes, before collecting an NMR spectrum. Hexamethyl benzene serves as an internal standard to quantitate the amount of Ru that comes off during the reaction (
TABLE-US-00003 TABLE 3 Quantification of GH2. A 1 (mg) 55.5 ISTD (mg) 9.0 GH2 (mg) 12.2 mmol/g Ru 0.22
Metathesis
Metathesis of 1-Decene
[0255] 1 (5 mg, 1.1 mol Ru) was added to a 20 mL reaction vessel, then charged with 0.5 mL of toluene. On a stir plate, 10 mL of 1.1M 1-decene in toluene is syringed into the reaction vessel. The final concentration of 1-decene is 1.05M, which contains 10000 equivalents of olefin per Ru. The reaction was monitored at regular time points by both GC-FID and NMR. A representative conversion plot obtained from NMR data for this metathesis experiment is shown in
TABLE-US-00004 TABLE 4 Conversion of 1-decene (also see FIG. 10). Percent Conversion Min. 1 3 4.2 5 13.3 10 22.0 15 35.7 30 54.8 60 74.1 120 85.5 240 91.6
TABLE-US-00005 TABLE 5 E/Z decene conversion with supported catalyst (also see FIG. 11). M720ASO Min. E Z 3 83.8 16.2 5 83.7 16.3 10 84.0 16.0 15 84.0 16.0 30 84.1 15.9 60 84.0 16.0 120 84.1 15.9 240 84.0 16.0
Leaching Experiment
[0256] 1 (5 mg, 1.1 mol Ru) and decene (154 mg, 1.1 mmol) were added to a micro reaction vessel. The neat reaction contains 1000 equivalents of olefin per Ru. After 3 minutes the entire reaction mixture was filtered through 3 separate pipette filters. An aliquot of the filtered reaction mixture was used to prepare an NMR inside of the glove box that was analyzed immediately and over the course of five days; no increase in metathesis or isomerization products were detected over the course of the experiment (
Maximum TON Experiment
[0257] 1 (5 mg, 1.1 mol Ru) and decene (180 mL, 0.95 mol) were added to a 350 mL Teflon sealed reaction vessel. The neat reaction contains >1,250,000 equivalents of olefin per Ru. A representative bar graph obtained from GC-FID data obtained at 35 days for this metathesis experiment is shown in
Metathesis of Allyltrimethylsilane
[0258] 1 (5 mg, 1.1 mol Ru) was added to a micro reaction vessel, then charged with 0.5 mL of toluene. On a stir plate, 1 mL of 1.1M allyltrimethylsilane in toluene is syringed into the reaction vessel. The final concentration of allyltrimethylsilane is 0.667M, which contains 1000 equivalents of olefin per Ru. The reaction was monitored at regular time points by both GC-FID and NMR. A representative conversion plot obtained from GC-FID data for this metathesis experiment is shown in
TABLE-US-00006 TABLE 6 Conversion of allyltrimethylsilane (also see FIG. 16). % Conversion Min. 1 3 16.4 5 19.6 10 25.7 15 26.7 30 29.2 60 29.8 120 30.8 240 32.7 480 36.1
Metathesis of allylbenzene
[0259] 1 (5 mg, 1.1 mol Ru) was added to a 20 mL reaction vessel, then charged with 0.5 mL of toluene. On a stir plate, 10 mL of 1.1M allylbenzene in toluene is syringed into the reaction vessel. The final concentration of allylbenzene is 1.05M, which contains 10000 equivalents of olefin per Ru. The reaction was monitored at regular time points by both GC-FID and NMR. A representative conversion plot obtained from GC-FID data for this metathesis experiment is shown in
TABLE-US-00007 TABLE 7 Allylbenzene metathesis conversion (also see FIG. 19). % Min. Conversion E Z 3 11.4 1.5 9.9 5 16.2 2.1 14.1 10 22.8 2.9 19.9 15 29.2 3.8 25.4 30 42.1 5.4 36.7 60 51.8 6.8 45.1 120 60.7 8.0 52.7 240 65.3 8.7 56.6 1440 70.8 9.2 61.6
TABLE-US-00008 TABLE 8 Allylbenzene metathesis % E/Z conversion (also see FIG. 20). M720ASO Min. E Z 3 18.5 81.5 5 15.2 84.8 10 15.3 84.7 15 14.2 85.8 30 14.8 85.2 60 14.6 85.4 120 14.3 85.7 240 13.7 86.3
Metathesis of Methyl Acrylate
[0260] 1 (5 mg, 1.1 mol Ru) was added to a micro reaction vessel, then charged with 0.5 mL of toluene. On a stir plate, 1 mL of 1.1M methyl acrylate in toluene is syringed into the reaction vessel. The final concentration of methyl acrylate is 0.667M, which contains 1000 equivalents of olefin per Ru. The reaction was monitored at regular time points by both GC-FID and NMR. A representative conversion plot obtained from GC-FID data for this metathesis experiment is shown in
TABLE-US-00009 TABLE 9 Conversion of methyl acrylate (also see FIG. 22). % Conversion Min. M720ASO 3 * 5 0.6 10 1.4 15 2.2 30 4.4 60 7.2 120 9.6 360 14.2
Ring-Closing Metathesis (RCM) of Dimethyl 2,2-diallyldimethyl malonate
[0261] 1 (5 mg, 1.1 mol Ru) was added to a J-Young NMR tube. 0.5 mL of 2.2 M 2,2-diallyldimethyl malonate (dimethyl diallylmalonate) in C.sub.6D.sub.6 is syringed into the NMR tube. The solution contains 1000 equivalents of olefin per Ru. The reaction was monitored by NMR (
TABLE-US-00010 TABLE 10 RCM reaction with supported catalyst. M720ASO GH2 Staring 90.9 93.4 material Product 9.1 6.6
Cross Metathesis of Allylbenzene and 1,4-diacetoxybutene
[0262] 1 (5 mg, 1.1 mol Ru) was added to a micro reaction vessel, then charged with 0.5 mL of toluene. On a stir plate, 0.5 mL of 2.2M allylbenzene in toluene and 0.5 mL of 4.4M 1,4-diacetoxybutene is syringed into the reaction vessel. The final concentration of each olefin is 0.73M and 1.47M respectively, which contains 1000 and 2000 equivalents of olefin per Ru. The reaction was monitored at regular time points by both GC-FID (
TABLE-US-00011 TABLE 11 cross metathesis reaction with the supported catalyst (also see FIG. 27). % Conversion CM Min. M720ASO GH2 3 66.2 62.2 5 66.3 63.9 10 67.0 65.0 15 67.9 66.9 30 68.4 68.2 60 68.5 70.6 120 71.2 70.6 240 72.9 71.1
Ethenolysis of Ethyl Oleate
[0263] 1 (5 mg, 1.1 mol Ru) and 1 mL of a 1.1M toluene solution of ethyl oleate was added to a 100 mL Teflon-valved flask, then charged with 0.5 mL of toluene. On a Schlenk line, the flask was freeze pump thawed and refilled with an atmosphere of ethylene. The reaction was stirred for 12 hours until the reaction was stopped, upon which (
TABLE-US-00012 TABLE 12 Ethenolysis reaction for the supported catalyst. M720AS GH 1 14. 15. 2 14. 14. 3 19. 19. 4 35. 34. 5 16. 16. 1) 1-decene 2) ethyl dec-9-enoate 3) octadec-9-ene 4) ethyl octadec-9-enoate (ethyl oleate and isomer, mainly the isomer) 5) diethyl octadec-9-enedioate
[0264] Additional catalysts and/or catalytic tests are also shown in
References in Example 1
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[0278] All publications, patents, and patent documents are incorporated by reference herein, as though individually incorporated by reference. The invention has been described with reference to various specific and preferred embodiments and techniques. However, it should be understood that many variations and modifications may be made while remaining within the spirit and scope of the invention.