Lipase-catalyzed hydrazine insertion for the synthesis of N′-alkyl benzohydrazides

N '-alkyl benzohydrazides are classic organic compounds that have been widely utilized in organic chemistry. In this study, an efficient method was developed for the synthesis of N '-alkyl benzohydrazides by hydrazine insertion catalyzed by lipase. Under the optimal conditions (Morita-Baylis-Hillman ketone [1 mmol], phenylhydrazine [1.3 mmol], N,N-dimethylformamide [2 ml], lipase [20 mg], room temperature, 12 h), satisfactory yields (71-97%) and substrate tolerance were obtained when porcine pancreatic lipase was used as biocatalyst. These findings imply the great potential for the lipase-catalyzed synthesis of N '-alkyl benzohydrazides and extend the utilization of lipase in organic chemistry.