Synthesis and structure of the lithium, zirconium and hafnium N-silyl-N′-benzyl-benzamidinates

The interaction of LiN(SiMe3)CH2Ph with one equivalent of benzenitrile gave the N-silyl-N′-benzyl-benzamidinato-lithium compound [{Me3SiNC(Ph)N(CH2Ph)}Li(Et2O)]2 (1). The derivative zirconium and hafnium compounds were produced by the treatment of 1 with ZrCl4 or HfCl4 in tetrahydrofuran or diethyl ether at ambient temperature, respectively, with the general formula [Me3SiNC(Ph)N(CH2Ph)]3MCl (M = Zr (2), Hf (3)). Compounds 1, 2 and 3 were also characterized by X-ray single crystal diffraction and NMR analysis.