A Facile and Stereoselective Synthesis of 3,4,6-Tri-O-Acetyl-2-Deoxy-2-Phthalimido-β-D-Glucopyranosyl Chloride

Abstract

Acetylation of D-glucosamine catalysed by sulfuric acid and N-phthaloylation of the glucosyl acetate yielded 1,3,4,6tetra-O-acetyl-2-deoxy-2-phthalimido-α-D-glucopyranose. This gave the corresponding pure β-glucosyl chloride upon treatment with PCl 5 -BF 3 . An anomeric chlorination with thionyl chloride combined with the Lewis acids (ZnCl 2 , SnCl 4 and BiCl 3 ) resulted in an α/β anomer mixture.