New chiral phosphorus ligands with spirobiindane backbone for asymmetric hydrogenations

Chiral spiro phosphorus ligands including monophosphoramidites and diphosphines, which contained 1,1'-spirobiindane as a backbone, were designed and synthesized. These spiro ligands were proven to be highly efficient for rhodium- and ruthenium-catalyzed asymmetric hydrogenations of prochiral olefins and ketones with excellent enantioselectivities.