Process for the synthesis of fluoralkyl sulfonate salts

Abstract

A process for the preparation of the fluoroalkyl sulfonate salt of a nitrogen-based organic base said process comprising the step of reacting a fluoroalkyl sulfonyl halide with an organic base selected from the group consisting of tertiary amines, pyridines, amidines and guanidines.

Claims

1. A process for the preparation of a fluoroalkyl sulfonate salt of any one of formula (VII), formula (VIII) or formula (IX): ##STR00006## ##STR00007## ##STR00008## wherein: R.sub.f is selected from the group consisting of C.sub.1 to C.sub.25 straight-chain, branched or cyclic fluorinated alkyl or alkenyl, optionally substituted and/or optionally comprising heteroatoms selected from the group consisting of O, N and S in the chain; each of R.sup.4, R.sup.5, R.sup.6, R.sup.7 and R.sup.8, is independently selected from the group consisting of H, halogen, C.sub.1 to C.sub.25 straight-chain, branched or cyclic, optionally substituted, alkane or alkene, and C.sub.6 to C.sub.25, optionally substituted, aryl or heteroaryl; each of R.sup.9, R.sup.10, R.sup.11 and R.sup.12, is independently selected from group consisting of H, C.sub.1 to C.sub.25 straight-chain, branched or cyclic, optionally substituted, alkane or alkene, optionally containing heteroatoms, wherein up to four of R.sup.9, R.sup.10, R.sup.11 and R.sup.12 may be bonded to one another in pairs by single or double bond; and each of R.sup.13, R.sup.14, R.sup.15, R.sup.16 and R.sup.17, is independently selected from the group consisting of H, C.sub.1 to C.sub.25 straight-chain, branched or cyclic, optionally substituted, alkane or alkene, optionally containing heteroatoms, wherein up to four of R.sup.13, R.sup.14, R.sup.15, R.sup.16 and R.sup.17 may be bonded to one another in pairs by single or double bond; said process comprising the step of reacting a fluoroalkyl sulfonyl halide with an organic base selected from the group consisting of: pyridines of formula (III): ##STR00009## amidines of formula (IV): ##STR00010## and guanidines of formula (V): ##STR00011## wherein R.sup.4-R.sup.17 are as defined above, in the presence of an alcohol when using a pyridine or amidine organic base; or in the presence of water under basic conditions when using a guanidine organic base.

2. The process of claim 1 wherein the fluoroalkyl sulfonyl halide is selected from the group consisting of the fluoroalkyl sulfonates of formula (I) R.sub.fSO.sub.2X, wherein X is selected from F, Cl and Br; and R.sub.f is selected from the group consisting of C.sub.1 to C.sub.25 straight-chain, branched or cyclic fluorinated alkyl or alkenyl, optionally substituted and/or optionally comprising heteroatoms selected from the group consisting of O, N and S in the chain.

3. The process of claim 1, wherein the fluoroalkyl sulfonyl halide is reacted with the organic base in the presence of an alcohol.

4. The process of claim 3 wherein the organic base is selected from the group consisting of pyridines and amidines.

5. The process of claim 3, wherein fluroalkyl sulfonates of formulae (VII) and (VIII) are prepared by reacting a fluoro alkyl sulfonate of formula (I) with pyridines of formula (III) and amidines of formula (IV), and an alcohol of formula ROH: ##STR00012## wherein R.sub.f is selected from the group consisting of C.sub.1 to C.sub.25 straight-chain, branched or cyclic fluorinated alkyl or alkenyl, optionally substituted and/or optionally comprising heteroatoms selected from the group consisting of O, N and S in the chain; each of R.sup.4, R.sup.5, R.sup.6, R.sup.7 and R.sup.8, is independently selected from the group consisting of H, halogen, C.sub.1 to C.sub.25 straight-chain, branched or cyclic, optionally substituted, alkane or alkene, and C.sub.6 to C.sub.25, optionally substituted, aryl or heteroaryl; each of R.sup.9, R.sup.10, R.sup.11 and R.sup.12, is independently selected from group consisting of H, C.sub.1 to C.sub.25 straight-chain, branched or cyclic, optionally substituted, alkane or alkene, optionally containing heteroatoms, wherein up to four of R.sup.9, R.sup.10, R.sup.11 and R.sup.12 may be bonded to one another in pairs by single or double bond; and R is selected from the group consisting of C.sub.1-C.sub.20 straight-chain, branched or cyclic, optionally substituted, alkyl optionally containing additional OH groups, and C.sub.6-C.sub.20 optionally substituted aryl or heteroaryl.

6. The process of claim 1, wherein the fluoroalkyl sulfonyl halide is reacted with the organic base in the presence of water under basic conditions.

7. The process of claim 6, wherein the organic base is a guanidine.

8. The process of claim 7, wherein a guanidinium fluoro alkyl sulfonate of formula (IX) is obtained: ##STR00013## wherein R.sub.f is selected from the group consisting of C.sub.1 to C.sub.25 straight-chain, branched or cyclic fluorinated alkyl or alkenyl, optionally substituted and/or optionally comprising heteroatoms selected from the group consisting of O, N and S in the chain; and each of R.sup.13, R.sup.14, R.sup.15, R.sup.16 and R.sup.17, is independently selected from the group consisting of H, C.sub.1 to C.sub.25 straight-chain, branched or cyclic, optionally substituted, alkane or alkene, optionally containing heteroatoms, wherein up to four of R.sup.13, R.sup.14, R.sup.15, R.sup.16 and R.sup.17 may be bonded to one another in pairs by single or double bond.

9. The process of claim 1, wherein R.sub.f is selected from the group consisting of C.sub.1 to C.sub.16 straight-chain, branched or cyclic fluorinated alkyl, optionally substituted and/or optionally comprising heteroatoms selected from the group consisting of O, N and S in the chain.

10. The process of claim 1, wherein R.sub.f is selected from CF.sub.3, CF.sub.2CF.sub.3, CF.sub.2CF.sub.2H, CF.sub.2CFHCl, C.sub.3F.sub.7, CF.sub.2CFHCF.sub.3, CF.sub.2CFHOCF.sub.3, CF.sub.2CF.sub.2OCF.sub.2CF.sub.3, CF.sub.2CFHOCF.sub.2CF.sub.3, CF.sub.2CF.sub.2OCFHCF.sub.3, CF.sub.2CF.sub.2OCF.sub.2CF.sub.2H, CF.sub.2CF.sub.2OCF.sub.2CF.sub.2CI, CF.sub.2CF.sub.2OCFClCF.sub.2Cl, CF.sub.2CFHOCF.sub.2CF.sub.2CF.sub.3, CF.sub.2CF.sub.2OCF.sub.2CF.sub.2OCF.sub.2CF.sub.2CF.sub.3, CF.sub.2CF.sub.2OCF(CF.sub.3)OCF.sub.2CF.sub.2CF.sub.3.

11. The process of claim 1, wherein R.sub.f is CF.sub.2CF.sub.2OCFClCF.sub.2Cl.

12. The process of claim 1, wherein the organic base is a pyridine of formula (III) and wherein: R.sub.4, R.sub.5, R.sub.6, R.sub.7 and R.sub.8 are all H; or R.sub.4 and R.sub.8 are CH.sub.3 and R.sub.5, R.sub.6, R.sub.7 are H; or R.sub.4, R.sub.6 and R.sub.8 are CH.sub.3 and R.sub.5 and R.sub.7 are H; or R.sub.4 and R.sub.6 are CH.sub.3 and R.sub.5, R.sub.7 and R.sub.8 are H.

13. The process of claim 1, wherein the organic base is an amidine selected from 1, 8-diazabicyclo[5.4.0]undec-7-ene, 1,5-diazabicyclo[4.3.0]non-5-ene, 2,9-diazabicyclo[4.3.0]non-1,3,5,7-tetraene, and 6-(dibutylamino)-1,8-diazabicyclo[5.4.0]undecene-7.

14. The process of claim 1, wherein the organic base is a guanidine selected from 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1,1-dimethylguanidine, 1,3-dimethylguanidine, 1,2-diphenylguanidine, 1,1,2-trimethylguanidine, 1,2,3-tricyclohexylguanidine, 1,1,2,2-tetramethylguanidine, guanine, 1,5,7-triazabicyclo[4.4.0]-dec-5-ene, 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene, 7-ethyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene, 7-n-propyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene, 7-isopropyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene, 7-n-butyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene, 7-cyclohexyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene, and 7-n-octyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene.

15. The process of claim 4, wherein the ratio of the fluoroalkyl sulfonyl halide to organic base is at least 1:2.

16. The process of claim 7, wherein the ratio of the fluoroalkyl sulfonyl halide to organic base is from 1:1 to 1:2.

Description

EXAMPLES 1, 2, AND 3

Synthesis of methyl-triethyl ammonium (1), tetrabutyl ammonium (2) and dimethyl-dibenzyl ammonium (3) 2-(perfluoroethoxy)perfluorethanesulfonate

(1) To a three-necked round bottom flask equipped with thermometer and stirring were added CH.sub.2Cl.sub.2 (60 mL) and CF.sub.3CF.sub.2OCF.sub.2CF.sub.2SO.sub.2F (10 g). The temperature of the mixture was brought to 0 C. Triethylamine (8.76 mL) was added and the mixture was allowed to stir at 0 C. for 30 minutes. Methanol (2.01 g) was added drop-wise. The temperature of the mixture was allowed to return to room temperature. After 2 hours the reaction was completed. The liquid phase was removed by evaporation under vacuum. The white solid was re-dissolved in CH.sub.2Cl.sub.2 (50 mL) and extracted with an aqueous NaOH solution (70 mL). The organic phase was separated from the aqueous phase. The aqueous phase was treated with Na.sub.2SO.sub.4 and the product recovered by evaporation under vacuum. Methyl-triethyl ammonium 2-(perfluoroethoxy)perfluorethanesulfonate (Example 1, 11.7 g) was isolated as a white solid in 87% yield (melting point 154 C.; 1% weight loss: 312 C.).

(2) .sup.19F NMR (HFMX reference): 84.1 ppm (m; 2F; OCF.sub.2CF.sub.2); 88.2 ppm (s; 3F; CF.sub.3); 90.1 ppm (m; 2F; CF.sub.3CF.sub.2O); 120.1 ppm (s; 2F; CF.sub.2SO.sub.3.sup.). .sup.1H NMR (TMS reference): +3.26 ppm (q; 6H; NCH.sub.2CH.sub.3); +2.88 ppm (s; 3H; CH.sub.3N); +1.22 ppm (m; 9H; NCH.sub.2CH.sub.3).

(3) Following a similar procedure, tetrabutyl ammonium 2-(perfluoroethoxy)perfluorethanesulfonate (Example 2, melting point 45.7 C.; 1% weight loss: 291 C.) was obtained in 59% yield from CF.sub.3CF.sub.2OCF.sub.2CF.sub.2SO.sub.2F (30 g), n-butanol (13.98 g) and tri(n-butyl)amine (34.97 g).

(4) .sup.19F NMR (HFMX reference): 84.1 ppm (m; 2F; OCF.sub.2CF.sub.2); 88.2 ppm (s; 3F; CF.sub.3); 90.1 ppm (m; 2F; CF.sub.3CF.sub.2O); 120.1 ppm (s; 2F; CF.sub.2SO.sub.3.sup.). .sup.1H NMR (TMS reference): +3.14 ppm (m; 8H; NCH.sub.2); +1.55 ppm (m; 8H; NCH.sub.2CH.sub.2); +1.28 ppm (m; 8H; C{right arrow over (H)}.sub.2CH.sub.3); +0.90 ppm (t; 12H; CH.sub.2CH.sub.3).

(5) Dimethyl-dibenzyl ammonium 2-(perfluoroethoxy)perfluorethanesulfonate (Example 3, melting point 62.3 C.; 1% weight loss: 289 C.) was obtained in 85% yield from CF.sub.3CF.sub.2OCF.sub.2CF.sub.2SO.sub.2F (25 g), benzyl alcohol (17.00 g) and dimethyl-benzyl amine (21.26 g) was obtained according to a similar procedure, the isolation of the product further comprising treatment with n-hexane for separation of the unreacted alcohol and amine.

(6) .sup.19F NMR (HFMX reference): 84.1 ppm (m; 2F; OCF.sub.2CF.sub.2); 88.2 ppm (s; 3F; CF.sub.3); 90.1 ppm (m; 2F; CF.sub.3CF.sub.2O); 120.1 ppm (s; 2F; CF.sub.2SO.sub.3.sup.). .sup.1H NMR (TMS reference): +7.55 ppm (m; 10H; Ph-); +4.58 ppm (s; 4H; NC H.sub.2Ph); +2.84 ppm (s; 6H; NCH.sub.3).

EXAMPLE 4

Synthesis of N-methyl-2,4,6-trimethyl-pyridinium 2-(perfluoroethoxy)perfluorethanesulfonate

(7) Following a procedure similar to the one described for Example 1, CF.sub.3CF.sub.2OCF.sub.2CF.sub.2SO.sub.2F (20 g) was reacted with 2,4,6-trimethylpyridine (15.24 g) in the presence of methanol (4.03 g) in CH.sub.2Cl.sub.2 (80 mL) at room temperature. N-methyl-2,4,6-trimethyl-pyridinium 2-(perfluoroethoxy)perfluorethanesulfonate (melting point 83.2 C., 1% weight loss: 323 C.) was isolated as a white solid in 87% yield.

(8) .sup.19F NMR (HFMX reference): 84.1 ppm (m; 2F; OCF.sub.2CF.sub.2); 88.2 ppm (s; 3F; CF.sub.3); 90.1 ppm (m; 2F; CF.sub.3CF.sub.2O); 120.1 ppm (s; 2F; CF.sub.2SO.sub.3.sup.). .sup.1H NMR (TMS reference): +7.70 ppm (s; 2H; meta-H); +3.96 ppm (s; 3H; NCH.sub.3); +2.72 ppm (s; 6H; ortho-CH.sub.3); +2.47 ppm (s; 3H; para-CH.sub.3).

EXAMPLE 5

Synthesis of N-methyl-1,8-diazabicyclo[5.4.0]undec-7-enium 2-(perfluoroethoxy)perfluorethanesulfonate

(9) Following a procedure similar to the one described for Example 1, CF.sub.3CF.sub.2OCF.sub.2CF.sub.2SO.sub.2F (27 g) was reacted with 1,8-diazabicyclo[5.4.0]undec-7-ene (16.80 g) in the presence of methanol (5.44 g) in CH.sub.2Cl.sub.2 at room temperature. A mixture of N-methyl-1,8-diazabicyclo[5.4.0]undec-7-enium 2-(perfluoroethoxy)perfluorethanesulfonate and 1,8-diazabicyclo[5.4.0]undec-7-enium 2-(perfluoroethoxy)perfluorethanesulfonate (melting point of the mixture 60 C.) was isolated as a yellow oil in 72.8% yield.

EXAMPLES 6 AND 7

Synthesis of 1,5,7-triazabicyclo[4.4.0]-dec-5-enium 2-(1,2-dichloro-1,1,2-trifluoroethoxy)perfluorethanesulfonate (6) and of N,N,N,N-tetramethylguanidinium 2-(1,2-dichloro-1,1,2-trifluoroethoxy)perfluorethanesulfonate (7)

(10) To a three-necked round bottom flask equipped with thermometer and stirring containing CH.sub.2Cl.sub.2 (305 g) and 1,5,7-triazabicyclo[4.4.0]-dec-5-ene (55.55 g) was added a solution of K.sub.2CO.sub.3 in water (4 M) followed by CF.sub.2ClCFClOCF.sub.2CF.sub.2SO.sub.2F (140.05 g), added drop-wise. The temperature of the mixture was kept to room temperature. After 2 hours the reaction was completed. A biphasic system was obtained. The organic phase was separated from the aqueous one, washed with water, treated with MgSO.sub.4 and any solid filtered off. The product was recovered by evaporation under vacuum in 84% yield (melting point 67 C.; 1% weight loss: 304 C.).

(11) .sup.19F NMR (HFMX reference): 70.9 ppm (d; 2F; ClCF.sub.2); 76.5 ppm (m; 1F; CFClO); 83.3 ppm (m; 2F; OCF.sub.2CF.sub.2); 118.5 ppm (s; 2F; CF.sub.2SO.sub.3.sup.). .sup.1H NMR (TMS reference): +3.30 ppm (m; 8H; NCH.sub.2); +2.00 ppm (m; 4H; CH.sub.2).

(12) Following a similar procedure, N,N,N,N-tetramethylguanidinium 2-(perfluoroethoxy)perfluorethanesulfonate (Example 7, melting point 71 C.; TGA 259 C.) was obtained in 98% yield from CF.sub.2ClCFClOCF.sub.2CF.sub.2SO.sub.2F (121.90 g) and N,N,N,N-tetramethylguanidine (40.00 g).

(13) .sup.19F NMR (HFMX reference): 70.9 ppm (d; 2F; ClCF.sub.2); 76.5 ppm (m; 1F; CFClO); 83.3 ppm (m; 2F; OCF.sub.2CF.sub.2); 118.5 ppm (s; 2F; CF.sub.2SO.sub.3.sup.). .sup.1H NMR (TMS reference): +2.95 ppm (s; 12H; CH.sub.3N).

(14) The inventive process thus provides a simple and convenient one-pot synthesis of fluoroalkyl sulfonate salts of nitrogen containing organic bases in high yields and purity.