Reaction of TiCl 2(TADDOLate)L 2 (L=THF ( 1) or AcOEt ( 2)) with a bidentate nitrogen-containing ligand such as 2,2 ′-bipyridine (bipy) or 1,10-phenanthroline (phen) affords six-coordinate complexes TiCl 2(TADDOLate)(L 2) (L 2=bipy ( 3) or phen ( 4)). Complexes 3 and 4 can also be obtained from reaction of 1.3 eq. of TiCl 4 with a TADDOL (α,α,α ′,α ′-tetraphenyl-1,3-dioxolane-4,5-dimethanol) ligand in diethyl ether followed by the addition of the bidentate ligand. The complex 3 reacts further with 2.2 eq. of MeLi in toluene to give the mono-methyl complex TiCl(Me)(TADDOLate)(bipy) ( 5). Complexes 3 and 4 were subjected to X-ray structural analyses and both structures reveal the same C 2 molecular symmetry with the bidentate bipy or phen ligand trans to the TADDOLate ligand. In the asymmetric reaction of diethylzinc addition to benzaldehyde, the monomeric metal complex 3 or 4 alone shows good catalytic reactivities with low to moderate enantioselectivities of 31% or 52% ee, respectively. However, with the addition of excess Ti(O- i-Pr) 4, the reaction gives nearly quantitative yields of the desired product with good enantioselectivities up to 88% ee.