Reactions of d0 alkylidene and amide complexes with silanes

Reactions of silanes with d(o) Ta alkylidene and Group 4 amide complexes were found to involve the initial attack on silicon atoms in the silanes by nucleophilic alkylidene carbon or amide nitrogen atoms. The reaction of (Me3SiCH2)(3)Ta(PMe3)[=CHSiMe3] (1) with H2SiR'Ph (R' = Me, Ph) gave (Me3SiCH2)(3)Ta[=C(SiMe3)SiHR'Ph] (2a-b). Similar reactions of these two silanes and (H2PhSi)(2)CH2 with (Me3SiCH2)Ta(PMe3)(2)[=CHR](2) (R = SiMe3, 3; CMe3, 4) yielded novel metallasilacyclobutadienes and a metalladisilacyclohexadiene, respectively. In comparison, the reactions between M(NMe2)(4) (M = Ti, Zr, Hf) and silanes were found to give aminosilanes and metal amide hydride species which were perhaps involved in the formation of titanium-silicon-nitride (Ti-Si-N) ternary materials.