Asymmetric hydrogenation of quinolines activated by Brّnsted acids

Enantioselective hydrogenation of quinolines and quinoxalines catalyzed by iridium/diphosphine complex with catalytic amount of Brّnsted acid as activator was developed. In the presence of piperidine·TfOH as the activator, full conversions and up to 92% ee were obtained.