Appel-reagent-mediated transformation of glycosyl hemiacetal derivatives into thioglycosides and glycosyl thiols

Abstract

A series of glycosyl hemiacetal derivatives have been transformed into thioglycosides and glycosyl thiols in a one-pot two-step reaction sequence mediated by Appel reagent (carbon tetrabromide and triphenylphosphine). 1,2-trans-Thioglycosides and β-glycosyl thiol derivatives were stereoselectively formed by the reaction of the in situ generated glycosyl bromides with thiols and sodium carbonotrithioate. The reaction conditions are reasonably simple and yields were very good.

Keywords

• Appel reagent
• carbon tetrabromide
• glycosyl hemiacetal
• glycosyl thiol
• thioglycoside
• triphenylphosphine