Copper-Catalyzed\nAerobic Oxidative Dehydrogenative\nCoupling to Access Benzo[<i>c</i>]cinnolines

In this paper, a highly efficient copper-catalyzed oxidative\ndehydrogenative\ncoupling to obtain benzo[<i>c</i>]cinnolines (up to 100%\nyield) was developed. It was found that DMAP was a highly efficient\nligand for copper-catalyzed oxidation, and molecular oxygen was a\ngreen oxidizing agent. In this simple process, various functional\ngroups were tolerated under mild reaction conditions, and the practicality\nof the process was demonstrated by the preparation of benzo[<i>c</i>]cinnolines on a gram scale and later derivatization.