Fluorosulfates of hexafluoroisobutylene and its higher homologs and their derivatives
View Patent ↗Hexafluoroisobutylene and its higher homologs are easily reacted with SO 3 to give fluorosulfates of the formula CH 2 ═C(R)CF 2 OSO 2 F, wherein R is a linear branched or cyclic fluoroalkyl group comprised of 1 to 10 carbon atoms and may contain ether oxygen. These compounds react under mild conditions with many nucleophiles to give CH 2 ═C(R)CF 2 X, where X is derived from the nucleophile. This reaction provides a route to many substituted hexafluoroisobutylenes, which copolymerize easily with other fluoro- and hydrocarbon monomers such as vinylidene fluoride and ethylene.
1. A process comprising contacting CH 2 ═C(R)CF 3 with SO 3 in the presence of a Lewis acid, wherein R is a linear, branched, or cyclic fluoroalkyl group comprised of 1 to 10 carbon atoms and may contain ether oxygen, to produce CH 2 ═C(R)CF 2 OSO 2 F.
2. A process comprising contacting CH 2 ═C(CF 3 ) 2 with SO 3 in the presence of a Lewis acid to produce a compound selected from the group consisting of CH 2 ═C(CF 3 )CF 2 OSO 2 F and CH 2 ═C(CF 2 OSO 2 F) 2 .
3. The process of claim 2 wherein the adduct produced in greatest yield is CH 2 ═C(CF 3 )CF 2 OSO 2 F.
4. The process of claim 2 wherein the adduct produced in greatest yield is CH 2 ═C(CF 2 OSO 2 F) 2 .
5. The process of claim 1 wherein the Lewis acid is selected from the group consisting of BF 3 , B(OCH 3 ) 3 , B(OR) 3 where R is an alkyl group, SbF 5 , SbCl 5 , BCl 3 , B(OC(═O)CF 3 ) 3 , B(OSO 2 CF 3 ) 3 , B 2 O 3 , H 3 BO 3 , and Na 2 B 4 O 7 .
6. The process of claim 1 wherein the Lewis acid is selected from the group consisting of BF 3 , B(OCH 3 ) 3 and SbF 5 .