Iridium(III)-catalyzed direct C-7 amination of indolines with organic azides

Abstract

Iridium-catalyzed regioselective C-7 amination of indolines has been achieved with organic azides as a facile nitrogen source. The developed procedure is convenient to perform even at room temperature and applicable to a wide range of substrates with high catalytic activity. Various types of organic azides (sulfonyl, aryl, and alkyl derivatives) were all successfully reacted under the present conditions as the viable reactant. Furthermore, indoline substrates bearing easily removable N-protecting groups such as N-Boc or N-Cbz could readily be employed, highlighting the synthetic utility of this methodology.