The First Generation and Stereospecific Alkylation of α-Trifluoromethyl Oxiranyl Anion

Generation and reactions of oxiranyl anion 2 stabilized by a trifluoromethyl group are described. Treatment of (S)-2,3-epoxy-1,1,1-trifluoropropane (75% ee) with n-BuLi followed by electrophiles gave corresponding 2-alkylated epoxide 3 with retention of stereochemistry in moderate to good yields. The reaction is applicable for a general synthesis of optically active trifluoromethylated tertiary alcohols.