Synthesis of 2,3-Disubstituted Indoles and Benzofurans by the Tandem Reaction of Rhodium(II)-Catalyzed Intramolecular C-H Insertion and Oxygen-Mediated Oxidation.

A highly effective and straightforward method to construct a wide range of functionalized 2,3-disubstituted indoles has been developed. The method involves the tandem reaction of rhodium(II)-catalyzed denitrogenative annulation of triazole-based benzyl anilines and oxygen-mediated oxidative aromatization. The developed method can also be used to synthesize 2,3-disubstituted benzofurans by replacing the benzyl anilines with benzyl phenols.