Rhodium-Catalyzed Asymmetric Hydrosilylation of Ketones Employing a New Ligand Embodying the Bis(oxazolinyl)pyridine Moiety

A general approach to new ligands embodying bis(oxazolinyl)pyridine has been developed, employing palladium-catalyzed Suzuki coupling and base-mediated cyclization as pivotal steps. A rhodium catalyst derived from the ligand 4-(4-ethylphenyl)-2,6-bis(4-isopropyl-4,5-dihydrooxazol-2-yl)pyridine gave excellent enantioselectivity in the asymmetric hydrosilylation of ketones. In addition the electronic effect of remote substituents on the catalytic activity of rhodium catalyst was studied.