Reactions of Epoxides Derived From 2′-(3″-Methylbut-2″-enyl)trifluoroacetanilides

Abstract

The intramolecular nucleophilic ring opening of the epoxides derived from 2′-(3″-methylbut-2″-enyl) trifluoroacetanilides has been investigated under both acidic and basic conditions. Boron trifluoride caused rearrangement of the epoxides to a ketone but no cyclization. Potassium carbonate in methanol caused regiospecific opening of the epoxides and generated dihydroindole products. The formation of a five-membered ring was confirmed by a single-crystal X-ray study of one of the products. The epoxides hydrolysed very readily in acidic conditions; the structure of one of the diol products was confirmed by a single-crystal X-ray study.