Gerald G. Vernice

Enantioselective synthesis of the volatile anesthetic desflurane

Abstract The first enantioselective synthesis of the commercial volatile anesthetic desflurane is reported. Treatment of ( R )-(−)-isoflurane with BrF 3 gives ( S )-(+)-desflurane with >96% inversion of configuration. This constitutes a correction of previously reported results.

Selective free-radical dechlorination of 1,1-dichloro-2,2,2-trifluoroethyl difluoromethyl ether initiated thermally or by uv light: A practical and ‘green’ method for isoflurane synthesis

Abstract Treatment of 1,1-dichloro-2,2,2-trifluoroethyl difluoromethyl ether ( 3 ) with 2-propanol followed by either irradiation with UV light or heating with radical initiators gives the inhalational anesthetic isoflurane. Unlike most other common dechlorination methods, monoreduction is the exclusive process and the by-products acetone and HCl are relatively benign. Some comments about the mechanism of the reduction will be presented, along with solutions to problems encountered during scale-up.