Preparation of chiral imidazolin-2-imine ligands and their application in ruthenium-catalyzed transfer hydrogenation

The reaction of 2-chloro-1,3-diisopropyl-4,5-dimethylimidazolium tetrafluoroborate with potassium fluoride and chiral diamines afforded bidentate chiral mono- and bis(imidazolin-2-imine) ligands, which were used for the complexation of the dicationic benzene-ruthenium complex fragment, [(η6-C6H6)Ru]2+. The resulting complexes were tested as catalysts for the transfer hydrogenation of acetophenone.127