Silicon Fluorides for Acid‐Base Catalysis in Glycosidations

Abstract

Abstract Adduct formation between alcohols as glycosyl acceptors and phenylsilicon trifluoride (PhSiF 3 ) as catalyst permits acid‐base‐atalyzed glycosidations with O ‐glycosyl trichloroacetimidates as glycosyl donors. In this way, from various glycosyl donors and acceptors 1,2‐ trans‐ and some 1,2‐ cis ‐glycosides could be obtained with high anomeric selectivity. A preference for an intramolecular bimolecular nucleophilic substitution (S N 2‐type) reaction course with concomitant donor and acceptor activation is supported by the results.