One-pot synthesis of hexias (6-O-acryl) cyclodextrin derivatives at room temperature

Abstract

A mild one-pot synthesis of hexias (6-O-acryl) cyclodextrin derivatives from per-O-benzyl-cyclodextrin was described. It was at room temperature that a regioselective conversion from benyl groups on the primary rim of cyclodextrin to the corresponding acryl groups was achieved with BF3·Me2O as catalyst and acrylic anhydride or acrylic chloride as acylating agent. The reaction was successfully applied in 6-O-acryl regioselective introduction from benzyl 2,3,4,6-tetra-O-benzyl-β-mannopyranoside as well. The products obtained can be valuable precursors for the thiol–ene click reaction or other further modification of carbohydrates.