Palladium-Catalyzed Intramolecular C–H Amination via Oxidative Coupling on Indole Derivatives: Access to 11H-Benzo[4,5]imidazo[1,2-a]indoles

A novel palladium-catalyzed intramolecular C-H amination via oxidative coupling exploiting inactivated N-substituted aryl amines on indoles for the one-pot synthesis of novel 11H-benzo[4,5]imidazo[1,2-a]indole derivatives is reported. The optimized reaction conditions accommodated a wide range of electronic variations on both the indole and the pendant aryl amine ring, resulting in products with good to excellent yields.