Electrocatalytic synthesis of nitriles from aldehydes with ammonium acetate as the nitrogen source

Abstract

A simple synthesis method of nitriles from corresponding aldehydes by electrochemical oxidation was developed with ammonium acetate as the nitrogen source and 4-acetamido- 2,2,6,6-tetramethylpiperidinyl-l-oxy (4-AcNH-TEMPO) as the catalyst. Cyclic voltammetry was performed to investigate the electrocatalytic activity of 4-AcNH-TEMPO for the conversion of benzaldehyde to benzonitrile. On the basis of in situ FTIR data and cyclic voltammetry experiments, a reaction mechanism, involving the redox of 4-AcNH-TEMPO and the generation of intermediate imine during the reaction, was proposed. This electrocatalytic reaction system provided an efficient protocol for synthesis of aromatic nitriles at room temperature with moderate to high yields.