US Patent H002234 Purification of desflurane containing R-123

A process for preparing 2-difluoromethoxy-1,1,1,2-tetrafluoroethane (desflurane) comprising the following steps:(a) providing a first mixture comprising desflurane and 2,2-dichloro-1,1,1-trifluoroethane (R-123);(b) adding water to the first mixture to form a second mixture; and(c) fractionally distilling the second mixture to yield a desflurane product purer in R-123 than said the mixture.Also described is a purified desflurane product prepared by the process, and intermediate products comprising water added to a mixture of desflurane and R-123.