Abstract

Treatment of Ti(cp)Cl3(cp = η5-C5H5) with SbCl5 as chloride abstractor in acetonitrile provided hexachloroantimonate(V) salts of Ti(cp)Cl2+, Ti(cp)Cl2+ and Ti(cp)3+ respectively. With 1:1 stoichiometry red-brown crystals of Ti(cp)Cl2(MeCN)3SbCl6 1 are obtained and with 1:2 stoichiometry light blue crystals of Ti(cp)Cl(MeCN)4SbCl62 2. Complete removal of chloride ion from Ti(cp)Cl3 requires a six-fold excess of SbCl5 when purple-blue crystals of Ti(cp)(MeCN)5SbCl63 3 can be isolated. These products were characterised by analytical and spectroscopic (IR, 1H NMR) data and, in the case of 3, by a crystal structure determination. Proton NMR studies indicate the presence of intermediate halide-bridged Ti(μ-Cl)2Sb species in solution during the sequential halide abstractions 1 � 2 � 3. Crystals of complex 3, obtained as the bis(solvate) from recrystallisation in acetonitrile, are monoclinic and X-ray structural analysis confirmed the formulation. The crystal structure space group Cc, a = 19.650(4), b = 19.182(4), c = 12.958(3) à , β = 91.612(3)°, Z = 4, R = 0.0386, R� = 0.0406 shows discrete cations and anions and a pseudo-octahedral co-ordination sphere for the TiIV. A significant trans influence of the cyclopentadienyl ligand affects Ti-N bond lengths in the complex.