A novel self-terminated Prins strategy for the synthesis of tetrahydropyran-4-one derivatives and their behaviour in Fisher indole synthesis

Abstract

A novel self-terminated Prins strategy has been developed for the synthesis of 2-substituted tetrahydropyran-4-one derivatives through a condensation of 3-(phenylthio)but-3-en-1-ol with carbonyl compounds in the presence of 5 mol% of Sc(OTf)₃ under mild conditions. A few products were subsequently transformed into the corresponding indoles by Fisher-indole synthesis.