Some Metal Halide – Phosphorus Halide – Alkyl Halide Complexes. Part III. The µ-Trihalohexahalodimetallate Ions of Titanium and Zirconium

Titanium tetrachloride reacts rapidly with trichloro-, tribromo- and methyldichlorophosphine in the presence of t-butyl chloride to give compounds containing a phosphonium cation R1R2PX2+ (R1 = t-butyl, R2 = chloride, bromide, or methyl, X = chloride or bromide) and the principal metal-containing anion, Ti2Cl9−. For tribromophosphine and t-butyl chloride a stoichiometric product, [ButPBr3][Ti2Cl9] was obtained which was characterized using vibrational spectroscopy. The other reactions gave non-stoichiometric materials, the sublimates of which may contain higher polymeric anions whilst the residues contained TiCl5− along with the parent dimeric anion.Zirconium tetrachloride and titanium tetrabromide reacted in a similar way to give the new ions Zr2Cl9− and Ti2Br9− in stoichiometric reactions.