Novel η3-1-Silaallyl Tungsten Complexes via Si−H Bond Activation of Hydrovinylsilanes: Structure and Reactivity toward Methanol

Reactions of cis-Cp*(CO)2W(MeCN)Me (1) with HSiMe2(CHCR2) (R = H, Me) afford the novel η3-1-silaallyl complexes Cp*(CO)2W(η3-Me2SiCHCR2) [R = H (2), Me (3)] accompanied by liberation of MeCN and CH4 via thermal Si−H bond activation. η3-Coordination and exo conformation of the 1-silaallyl ligand in 3 are shown by X-ray crystal analysis, which reveals the partial double bond character of the Si−C bond (1.800(4) A) in the silaallyl moiety. Complexes 2 and 3 show extremely high reactivity toward MeOH to give the hydrido-(methoxysilyl)alkene complex trans-Cp*(CO)2WH(η2-MeOMe2SiCHCH2) (4) and the four-membered metallacycle (6), respectively.