Reactivity of per-O-acetylated 1-thioglycosides and glycosyl sulfones towards chromium(II) complexes in aqueous medium

Anomeric carbon-sulfur bonds in 1-thioglycosides and glycosyl sulfones can be cleaved by chromium(II) complexes in water-DMF medium. Anomeric radicals as well as sugar-chromium(III) complex intermediates can be generated in these reactions, leading in some cases, to the exclusive formation of the corresponding glycals.