Preparation and characterization of (C5Me4Ph)TiCl3, the oxochloride complexes [(C5Me4Ph)TiCl2](2)(mu-O) and [(C5Me4Ph)TiCl(mu-O)](3) and the oxo-complex [(C5Me4Ph)Ti](4)(mu-O)(6). The X-ray crystal structures of [(C5Me4Ph)TiCl2](2)(mu-O) and [(C5Me4Ph)Ti](4)(mu-O)(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)(mu-O) (2) and [(C5Me4Ph)TiCl(mu-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) Angstrom, beta = 124.06(5)degrees) consists of trans [(C5Me4Ph)TiCl2](2)(mu-O) molecules of C-2 symmetry with nearly linear Ti-O-Ti units (169.3(2)degrees). Reaction of 1 with an excess of H2O/HNEt2 results in the formation of the oxo-complex [(C5Me4Ph)Ti](4)(mu-O)(6) (4). The X-ray crystal structure of 4 (triclinic, space group P (1) over bar, a = 11.861(5), b = 12.706(5), c = 18.218(8) Angstrom, alpha = 87.58(3)degrees, beta = 89.00(3)degrees, gamma = 86.60(3)degrees) 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. (C) 1997 Elsevier Science S.A.