Iridium(III)-Catalyzed Tandem Annulation of Pyridine-Substituted Anilines and α-Cl Ketones for Obtaining 2-Arylindoles

Abstract

A facile and expeditious protocol for the synthesis of 2-arylindoles compounds from readily available N-(2-pyridyl)anilines and commercially available α-Cl ketones through iridium-catalyzed C-H activation and cyclization is reported here. As a complementary approach to the conventional strategies for indole synthesis, the transformation exhibits powerful reactivity, tolerates a large number of functional groups and proceeds in good to excellent yields under mild conditions, providing a straightforward method to access structurally diverse and valuable indole scaffolds. Further, the reaction could be easily scaled up to gram scale.