Reaction of Mono‐ and Bidentate Phosphane Oxides with TiCl ₄ and Ti(NMe ₂ ) ₄

The addition of secondary Mes 2 P(O)H and of bulky tertiary phosphindole oxide onto TiCl 4 leads to formation of trans ‐[TiCl 4 (OPR 3 ) 2 ] 1 and 2 . Contrary to this finding, Ti(NMe 2 ) 4 metalates secondary dimesitylphosphane oxide and mixtures of the mononuclear complexes [Ti(NMe 2 ) 4− n (OPMes 2 ) n ] form. The ratio between the amido and phosphinito ligands varies with the stoichiometry; however, pure compounds are not accessible. Fast ligand exchange reactions interconvert these complexes and only mixtures are obtained. The reaction of TiCl 4 with bidentate alkane‐α,ω‐diyl‐bis(diarylphosphane oxides), Ar 2 P(O)–(CH 2 ) n –P(O)Ar 2 with Ar/n = Ph/1 ( I ), Ph/2 ( II ), and Mes/2 ( III )) yields insoluble [( I ) 2 Ti 2 Cl 4 (μ‐Cl) 2 ] [Ti 2 Cl 9 ] 2 ( 3 ), [( II ) 2 TiCl 2 ] [Ti 2 Cl 9 ] 2 ( 4 ), and [( III ) 2 (TiCl 3 ) 2 ] [Ti 2 Cl 9 ] 2 ( 5 ) regardless of the applied stoichiometry. All these complexes have the dinuclear [Cl 3 Ti(μ‐Cl) 3 TiCl 3 ] − anion in common.