Ligation studies of titanium–phenoxide and –dimethylamide derivatives with covalent metal halides: a route to binuclear transition-metal complexes

Abstract

Convenient and high-yield syntheses for [Ti(cp)(OPh)₃] and [Ti(cp)Cl(OPh)₂](cp =η-C₅H₅) are described. The donor characteristics of the mixed phenoxides [Ti(cp)_n(OPh)_{4 –n}], n= 0, 1, or 2, [{TiCl₂(OPh)₂}₂], [Ti(cp)Cl(OPh)₂], and of Ti(NMe₂)₄ have been investigated. Reactions with MCl₃(M = Ti, V, or Cr), VOCl₃, MX₄(M = Ti, Zr, Hf, or Sn; X = Cl or Br), and MCl₅(M = Nb, Ta, or Mo) generally feature exchange of OPh and NMe₂ groups with halide rather than complexation. In several instances, using appropriate reaction conditions, the solid adducts MX₄·Ti(NMe₂)₄(M = Sn, X = Cl or Br; M = Zr or Hf, X = Cl), SnCl₄·[Ti(cp)₂(OPh)₂], and ZrCl₄·Ti(OPh)₄ have been isolated and fully characterised by analytical and spectral data.