Enantioselective C–H Annulation of Indoles with Diazo Compounds through a Chiral Rh(III) Catalyst

The asymmetric C–H annulation of O-pivaloyl 1-indolehydroxamic acid with donor/acceptor diazo compounds has been achieved for the first time, to the best of our knowledge, by using a rhodium catalyst embedded in a chiral binaphthyl backbone. This protocol constitutes a straightforward route for the synthesis of a new family of 1,2-dihydro-3H-imidazo­[1,5-a]­indol-3-one derivatives having a quaternary carbon stereocenter in high yields and excellent enantioselectivity (up to 98:2 er).