1,1,1,3,3-Pentafluoro-2-(fluoromethoxy)-3-methoxy-propane is fluorinated diether derivative of anestehtic sevoflurane treated with bromine trifluoride. 1,1,1,3,3-Pentafluoro-2-(fluoromethoxy)-3-methoxy-propane is a sedative/hypnotic in animal when administered I.V.