Synthesis of Deoxy Pyranosides Via Fe(III) Catalyzed Regioselective Thiocarbonylation of Partially Protected Carbohydrates

Abstract

AbstractRapid and efficient synthesis of targeted deoxygenated glycosides is highly desired. Herein, we disclose a two‐step procedure for the synthesis of deoxysugars from partially protected pyranosides via site‐selective thiocarbonylation followed by tin‐free Barton–McCombie deoxygenation. The selectivity can be smoothly achieved through anhydrous FeCl3 as the catalyst assisted by low‐priced benzoyltrifluoroacetonate (Hbtfa) ligand in the presence of K2CO3 as base. Further deoxygenation can be carried out using greener silicon reagent, avoiding highly toxic organotin reagents in traditional procedures. Conspicuous features of this method include mild conditions, easy operation, high selectivity and non or low toxic reagents, making it a more attractive strategy.