Cobalt/Photoredox Dual-Catalyzed Alkylation of Indole with Unactivated Alkenes

We herein report an efficient and scalable alkylation of indole with unactivated alkenes via a dual photoredox- and cobalt-catalyzed metal hydride hydrogen atom transfer (MHAT) and radical-polar crossover process. The reaction features a broad substrate scope and good functional group tolerance, providing access to structurally diverse C3-alkylated indole derivatives in good to excellent yields. This work offers a new strategy for the highly selective alkylation of indoles without restrictions on any reaction components and represents an important complement to existing MHAT-mediated alkene hydrofunctionalization with nucleophiles.