1-(Acyloxy)benzotriazoles: Useful Reagents for the Regioselective Acylation of Diols

Abstract

Acylated derivatives of 1-hydroxybenzotriazole (HOBt) have been widely used as reactive intermediates in a variety of one-pot, bond forming reactions. Isolable benzotriazole 'esters' 1-(benzoyloxy)benzotriazole (1-BBTZ, 1) and 1-(acetoxy)benzotriazole (2) are also useful reagents for the regioselective acylation of diols and partially protected carbohydrates (Fig. 1).[¹] 1-(Acyloxy) benzotriazoles 1 and 2 can be conveniently prepared by a carbodiimide-promoted condensation of HOBt,[²] or via the corresponding acyl chloride.[¹]