New route to biaryl phosphanes with axial chirality as ligands for enantioselective hydrogenations

We have found a modular route for the synthesis of Cl-MeO BIPHEP ligands via the corresponding biphenol that allows us to introduce several substituents without the necessity to separate the enantiomers of each derivative. These new diphosphanes were used in the ruthenium-catalyzed enantioselective hydrogenation of dimethyl itaconate with ee values up to 97%.