Nickel-Catalyzed <i>trans</i>-Carboamination across Internal Alkynes to Access Multifunctionalized Indoles

Abstract

A Ni-catalyzed reaction was developed for the synthesis of multifunctionalized indoles. The reaction proceeded through oxidative cyclization of the Ni(0)/P^N complex with an enyne system, 2-alkynyl anilinoacrylate, to provide a nickelacycle intermediate. The trans-carboamination around the internal alkyne was achieved by syn/anti-rotation of the Ni-carbenoid intermediate formed by C–N bond cleavage of the nickelacycle, and 3-alkenylated indoles were formed by C–N bond-forming reductive elimination. Notably, the synthesized indoles could be successfully transformed to functionalized carbazoles.

Topics & Concepts