Nitriles as Solvents in Glycosylation Reactions: Highly Selective β-Glycoside Synthesis¹

Abstract

Treatment of glycosyl trichloroacetimidates in nitriles as solvent at low temperatures with trimethylsilyl trifluoro-methanesulfonate (SN1-type conditions) leads under α-face attack to fast nitrilium-nitrile conjugate formation. These intermediates are converted rapidly in the presence of various acceptors into β-disaccharides in high yields and diastereoselectivities.