Electrochemical trifluoromethylation of acrylonitrile and crotonitrile. Preparation of 2,3-bis(2,2,2-trifluoroethyl)succinonitrile and 3,4-dicyano-2,5-bis(trifluoromethyl)-n-hexane

Abstract Electrooxidation of trifluoroacetic acid in the presence of acrylonitrile in an acetonitrile-water solution, followed by simple steam distillation of the reaction mixture, provided almost pure 2,3-bis(2,2,2-trifluoroethyl)succinonitrile in a 20 – 25% yield and in a 1 : 1 diastereoisomers ratio. The meso isomer has been isolated and its structure confirmed by X-ray analysis. Similarly, the reaction in the presence of crotonitrile gave a diastereoisomeric mixture of 3,4-dicyano-2,5-bis(trifluoromethyl)-n-hexanes albeit in lower yield.