Reaction of 5-(Trifluoromethyl)-2(5H)-furanone under Basic Conditions: Stereo-Controlled Michael Dimerization

Treatment of 5-trifluoromethyl-2(5H)-furanone under basic conditions gave a stereoisomeric mixture of two out of four possible stereoisomers of bis(trifluoromethyl)dihydro-2,4-bisfuranonyl depending on the reaction conditions. Butenolide anion generated with LDA is kinetically stable and reaction with 2-cyclohexenone stereoselectively gave a Michael adduct.