Ligand-Accelerated, Copper-Catalyzed Aerobic Oxidative Dehydrogenation of Primary Amines to Nitriles.

A highly efficient copper-catalyzed oxidative dehydrogenation of primary amines to access nitriles has been developed. We found that DMAP was an efficient ligand for copper-catalyzed oxidation and molecular oxygen was a green oxidizing agent. This reaction exhibited excellent functional group compatibility and a broad substrate scope. Various benzylic, allylic, and aliphatic amines were selectively and effectively oxidized to the corresponding nitriles in high yields (up to 100%). The ligand DMAP not only accelerated the reaction rate but also enhanced the stability of the catalyst. The practicality of the reaction was illustrated on a gram scale, even at a lower catalyst loading and/or under bubble air conditions.