Optically active titanium complexes containing linked amido-cyclopentadienyl ligands: Their use as asymmetric catalysts

Article abstract of DOI:10.1002/cber.19961291205

Optically active titanium complexes of the formula Ti[η⁵:η¹-C₅R₄SiMe ₂NCHMePh)Cl₂ (R = H, Me), containing the cyclopentadienyl ligand linked to a chiral 1-phenylethylamido moiety, were synthesized and characterized in both enantiomerically pure forms. A single-crystal X-ray structural analysis of (S)-(-)Ti(η⁵:-C₅H₄SiMe ₂NCHMePh)Cl₂ shows a con-formation in which the phenyl group is turned away from the rnetal center. NOE measurements suggest that a related structure is retained in solution. Upon activation with n-butyllithium, these complexes show hydrogenation activity toward imines with slight enantioselectivity. VCH Verlagsgesellschaft mbH, 1996.