Preparation and characterization of (C5Me4Ph)TiCl3, the oxochloride complexes [(C5Me4Ph)TiCl2]2( μ-O) and [(C5Me4Ph)TiCl( μ-O)]3 and the oxo-complex [(C5Me4Ph)Ti]4( μ-O)6

Article abstract of DOI:10.1016/S0022-328X(97)00327-6

The titanium compound (C₅Me₄Ph)TiCl₃ (1) can be prepared by the reaction of (C₅Me₄Ph)SiMe₃ with TiCl₄. Hydrolysis of 1 in the presence of HNEt₂ or Ag₂O has allowed for the isolation of the oxochloride complexes [(C₅Me₄Ph)TiCl₂]₂( μ-O) (2) and [(C₅Me₄Ph)TiCl( μ-O)]₃ (3), respectively. The NMR spectra of 3 are consistent with a nearly flat Ti₃O₃ ring having down-up-up or E-Z-Z arrangement of (C₅Me₄Ph)-ligands around the ring. The X-ray crystal structure of 2 (monoclinic, space group C2/c, a = 19.847(12), b = 9.089(5), c = 20.405(13) A, β = 124.06(5)°) consists of trans [(C₅Me₄Ph)TiCl₂]₂( μ-O) molecules of C₂ symmetry with nearly linear Ti-O-Ti units (169.3(2)°). Reaction of 1 with an excess of H₂O/HNEt₂ results in the formation of the oxo-complex [(C₅Me₄Ph)Ti]₄( μ-O)₆ (4). The X-ray crystal structure of 4 (triclinic, space group P1, a = 11.861(5), b = 12.706(5), c = 18.218(8) A, α = 87.58(3)°, β = 89.00(3)°, γ = 86.60(3)°) reveals that the molecules of 4 have an adamantane-like Ti₄O₆ cage of nearly T_d symmetry. The NMR spectra and molecular structures of 1, 2, 3 and 4 are discussed.