Diverse cyclization catalyzed by in(OTf)3 for the convergent assembly of substituted tetrahydrofurans and tetrahydropyrans

Abstract

(Equation presented) A novel In(OTf)3-catalyzed (3,5) oxonium-ene type cyclization for the facile construction of various multisubstituted tetrahydrofurans and tetrahydropyrans was successfully developed. Further mechanistic investigations unveiled an In(OTf)3-catalyzed skeletal reorganization of the tetrahydrofuran to its thermodynamic isomer under thermal conditions.