Development of chiral ferrocenyl P,P,N,N,O-ligands for ruthenium-catalyzed asymmetric hydrogenation of ketones

Abstract

A new type of ferrocenyl P,P,N,N,O-ligand has been developed through a one-step transformation. This represents a rare example of a ligand containing both chiral bisphosphine and diamine groups suitable for ruthenium-catalyzed asymmetric hydrogenation. Its ruthenium complex can be directly prepared by stirring the ligand and [Ru(benzene)Cl₂]₂ at 90 °C in DMF for 4 hours. The catalyst showed high reactivity and enantioselectivity in the hydrogenation (AH) of simple ketones and α,β-unsaturated ketones, providing the corresponding chiral aryl alkyl alcohols and chiral allyl alcohols with up to 99% yield and 96% ee.