Electrocatalytic intramolecular oxidative annulation of N-aryl enamines into substituted indoles mediated by iodides.

An electrocatalytic reaction protocol is developed for achieving intramolecular dehydrogenative annulation of N-aryl enamines. It offers a simple and efficient way for the synthesis of indoles in an undivided cell. Good to excellent yields are obtained under oxidant-free and transition-metal-free conditions. Moreover, imidazo[1,2-a]pyridines could also be produced when N-pyridyl enamines were used as the substrates.