Enantioselective Hydrophosphination of Enones with Diphenylphosphine Catalyzed by Bis(imidazoline) NCN Pincer Palladium(II) Complexes

A series
of chiral NCN pincer Pd­(II) complexes with 1,3-bis­(2′-imidazolinyl)­phenyl
(Phebim) ligands were synthesized via the C–H activation or
oxidative addition method. A dinuclear macrocyclic Pd­(II) complex
was also prepared by reaction of the Phebim-H ligand with PdCl2. All of the new compounds were fully characterized, and X-ray
single-crystal structures were obtained for two of the complexes.
The Pd­(II) complexes were successfully applied to enantioselective
hydrophosphination of various enones with diphenylphosphine, providing
optically active phosphine derivatives in good yields with enantioselectivities
of up to 94% ee.