MONOCYCLOPENTADIENYLCHLOROOXOTITANIUM(IV) DIMERS, TRIMERS AND TETRAMERS

High-yield syntheses (greater-than-or-equal-to 90%) of the monocyclopentadienyloxochloro complexes [(TiLCl2)2(mu-O)] 2, [(TiLCl)4(mu-O)4] 3, [(TiL)4(mu-O)6] 4 and [(TiLCl)3(mu-O)3] 5 have been achieved by hydrolysis of the precursors [TiLCl3] 1 [L = eta(5)-C5H5, C5H4Me, C5H4(SiMe3) or C5Me5]. In addition [Ti{eta(5)-C5H4(SiMe3)}Br3] 7, [Ti4{eta(5)-C5H4(SiMe3)}4Br4(mu-O)4] 8 and [Ti4{eta(5)-C5H4(SiMe3)}4(NCS)4(mu-O)4] 9 have been prepared. The structures of the cyclic trimer 5 (L = eta(5)-C5Me5) and tetramer 9 have been determined by X-ray analysis: 5, monoclinic, space group P2(1)/c, a = 16.724(2), b = 8.958(1), c = 22.871(2) angstrom, beta = 91.73(1)-degrees, Z = 4 and R = 0.065 for 3159 independent observed reflections; 9, monoclinic, space group Cc, a = 24.527(2), b = 12.520(2), c = 18.931(2) angstrom, beta = 115.46(2)-degrees, Z = 4 and R = 0.060 for 3088 independent observed reflections. The electronic configurations of complexes 2-5 have been calculated by extended-Huckel molecular orbital calculations.