DBN‐Catalyzed Regioselective Acylation of Carbohydrates and Diols in Ethyl Acetate

Abstract

The 1,5‐diazabicyclo[4.3.0]non‐5‐ene (DBN)‐catalyzed regioselective acylation of carbohydrates and diols in ethyl acetate has been developed. The hydroxyl groups can be selectively acylated by the corresponding anhydride in EtOAc in the presence of a catalytic amount (as low as 0.1 equiv.) of DBN at room temperature to 40 °C. This method avoids metal catalysts and toxic solvents, which makes it comparatively green and mild, and it uses less organic base compared with other selective acylation methods. Mechanism studies indicated that DBN could catalyze the selective acylation of hydroxyl moieties through a dual H‐bonding interaction.