Asymmetric iridium-catalyzed hydrogenation of 2-methylindole using phosphite ligands

•Ir-catalyzed asymmetric hydrogenation of 2-methylindole.•Use of monodentate phosphite and amidophosphite ligands.•Use of iodine as the additive resulted in increased enantioselectivity. The iridium-catalyzed asymmetric hydrogenation of 2-methylindole using monodentate phosphites and amidophosphites as ligands was examined. The use of iodine as the additive resulted in increased enantioselectivity and conversion in the iridium-catalyzed hydrogenation of 2-methylindole. Full conversion and up to 80% ee were obtained with a catalyst based on a phosphite ligand.