Reaction of metallocene dichlorides of titanium(IV) and zirconium(IV) and lithium bis(trimethylsilyl)amide

Reaction of Cp2TiCl2 with 1 or 2 molar equiv of LiN(SiMe3)2 yields the previously described metallacycle Cp2TiCH2SiMe2NSiMe3. Mass balance shows that for each mole of metallacycle formed, 1 molar equiv of hydrogen chloride is also formed. The related zirconium metallacycle was prepared from Cp2Zr(H)(Cl) and LiN(SiMe3)2. The bis(silylamide) of zirconium, Cp2Zr[N(SiMe3)2]2, was prepared from Cp2ZrCl2 and 2 molar equiv of LiN(SiMe3)2. The Me3Si groups in the latter compound are magnetically nonequivalent at 270C but coalesce at 840C on the 1H NMR time scale