Rhodium(iii)-catalyzed indole synthesis at room temperature using the transient oxidizing directing group strategy

Abstract

Rh-catalyzed reactions of N-alkyl anilines with internal alkynes at room temperature have been developed using an in situ generated N-nitroso group as a transient oxidizing directing group. Due to mild reaction conditions, this method enabled synthesis of a broad range of N-alkyl indoles, including even two indole-based medicinal compounds. Our work disclosed the feasibility of the transient oxidizing directing group strategy in C–H functionalization reactions, which possesses the potential to enhance overall step-economy and impart new reactivity patterns to substrates.