o-Acetoxylation of oxo-benzoxazines via C–H activation by palladium(ii)/aluminium oxide

Abstract

Direct activation of sp² C–H bonds by a palladium catalyst has received significant attention in organic chemistry. However, most of these C–H activation reactions are carried out in hazardous solvents. Herein we report a novel solvent-free direct sp² C–H bond functionalization (oxygenation) method using Pd(II)/Al₂O₃ catalysis of oxo-benzoxazine derivatives with good to excellent yields, and demonstrate its application in the synthesis of pharmaceutically important compounds.