Asymmetric hydrogenation of quinolines with high substrate/catalyst ratio

The chiral diphosphinite ligand derived from (R)-1,1'-spiro-biindane-7,7'-diol has been found to be highly effective in the Ir-catalyzed asymmetric hydrogenation of quinolines with high substrate/catalyst ratio (up to 5000) and high enantioselectivity (up to 94% ee).