Ligand-Free Nickel-Catalyzed Arylation Cascades for Accessing Pyrrolopyridin-2-one, Pyranoindole-2,7-dione, and Indolin-2-one Frameworks with Mechanistic Insights

Abstract

A ligand-free nickel-catalyzed tandem carbocyclization-arylation reaction enables regioselective access to aryl-and heteroarylfused lactams in a one-pot process. Broad substrate tolerance affords indolin-2-one, pyrrolo[3,2-b]pyridin-2-one, and coumarinfused lactam frameworks. Mechanistic analysis and DFT calculations support a Ni(I)/Ni(III) catalytic pathway proceeds through sequential C-Br activation and alkyne carbocyclization.