An efficient catalyst system for the asymmetric transfer hydrogenation of ketones: remarkably broad substrate scope.
A BINOL-derived diphosphonite having a xanthene backbone is an excellent bidentate ligand in Ru-catalyzed 2-propanol-based transfer hydrogenation of aryl/alkyl and alkyl/alkyl ketones (ee = 76-99%). Even notoriously difficult ketones such as isopropyl methyl ketone are reduced with extraordinarily high enantioselectivity (ee = 99%).
Reetz
Manfred T
MT
Max-Planck Institut für Kohlenforschung, Mülheim/Ruhr, Germany. reetz@mpi-muelheim.mpg.de
Li
Xiaoguang
X