Cobalt-Catalyzed Acceptorless Dehydrogenation of Primary Amines to Nitriles

J Am Chem Soc. 2024 May 1;146(17):11801-11810. doi: 10.1021/jacs.4c00493. Epub 2024 Apr 16.

Abstract

The direct double dehydrogenation from primary amines to nitriles without an oxidant or hydrogen acceptor is both intriguing and challenging. In this paper, we describe a non-noble metal catalyst capable of realizing such a transformation with high efficiency. A cobalt-centered N,N-bidentate complex was designed and employed as a metal-ligand cooperative dehydrogenation catalyst. Detailed kinetic studies, control experiments, and DFT calculations revealed the crucial hydride transfer, proton transfer, and hydrogen evolution processes. Finally, a tandem outer-sphere/inner-sphere mechanism was proposed for the dehydrogenation of amines to nitriles through an imine intermediate.