A facile synthesis of per-O-alkylated glycono-delta-lactones from per-O-alkylated glycopyranosides and a novel ring contraction for pyranoses

A novel one-pot synthesis of a variety of O-peralkylated delta-aldonolactones 9 from their corresponding glycosides 1 is introduced. This facile procedure involves combining glycoside precursor, tin(IV) chloride and trimethylsilyl azide in methylene chloride at room temperature to furnish the title compounds in moderate to high yields. A side reaction involving extrusion of C-1 of the common carbohydrate intermediate leads to D-arabinofuranoside and D-lyxofuranoside derivatives 10a and 10b respectively. (C) 1997 Elsevier Science Ltd.