The reactivity of trimethylsilyliminophosphines towards titanium and zirconium halides

Abstract

Zirconium tetrachloride reacted with C₂H₄(Ph₂PNSiMe₃)₂-1,2 1 under C–H activation to give the NCN chelate complex ZrCl₃{κ³-N,C,N′-C₂H₃(Ph₂PNSiMe₃)₂}, while the reaction with C₅H₃N(Ph₂PNSiMe₃)₂-2,6 gave an N-donor adduct. Cp*TiCl₃ reacts with trimethylsilyliminophosphines under dehalosilylation in all cases. In contrast to 1, the potentially C–N chelating benzylphosphinimine (4-Bu^tC₆H₄CH₂)Ph₂PNSiMe₃ undergoes dehalosilylation with TiCl₄ in preference to C–H activation, while prolonged reflux with ZrCl₄ affords the salt [4-Bu^tC₆H₄CH₂P(Ph)₂NHSiMe₃]₂[Zr₂Cl₁₀]. The molecular structures of the latter, ZrCl₃{C₂H₃(Ph₂PNSiMe₃)₂}, C₅H₃N(Ph₂PNTiCl₂Cp*)₂-2,6, and TiCl₂Cp*{NPPh₂CH₂C₆H₄Bu^t-4} have been determined by X-ray diffraction.