Department of Chemistry, Graduate School of Science, Tohoku University, Aoba-ku, Sendai 980-8578, Japan.
Chem Asian J. 2012 Jun;7(6):1408-16. doi: 10.1002/asia.201101058. Epub 2012 Mar 22.
Reaction of a labile tungsten nitrile complex, [(Cp*)W(CO)(2)(NCMe)Me] (Cp*=η(5)-C(5)Me(5)), with H(3)SiC(SiMe(3))(3) gave the hydrido(hydrosilylene) complex [(Cp*)(CO)(2)(H)W=Si(H){C(SiMe(3))(3)}] (1a). The hydrido(silylene) complex [(η(5)-C(5)Me(4)Et)(CO)(2)(H)W=SiMes(2)] (2) (Mes=2,4,6-Me-C(6)H(2)) was synthesized by a similar reaction with H(2)SiMes(2). There is a strong interligand interaction between the hydrido and silylene ligands of these complexes; this was confirmed by a neutron diffraction study of [D(2)]1b, that is, the deuterido and η(5)-C(5)Me(4)Et derivative of 1a. The exchange between the W-H and the Si-D groups was observed in the deuterido complex [D]1a. This H/D exchange proceeded slowly at room temperature, but very rapidly under UV irradiation. Variable-temperature NMR spectroscopy measurements show the dynamic behavior of carbonyl ligands in 1a. Complex 1a reacted with acetone at room temperature to give mainly a hydrosilylation product, [(Cp*)(CO)(2)(H)W=Si(OiPr){C(SiMe(3))(3)}] (3a), along with a siloxy complex, [(Cp*)(CO)(2)WO(Si(H)iPr{C(SiMe(3))(3)})] (4a). At low temperature, a different reaction, namely, α-H abstraction, proceeded to give an equilibrium mixture of 1a and a dihydrido(silyl) complex, [(Cp*)(CO)(2)(H)(2)W(Si(H){OC(=CH(2))Me}{C(SiMe(3))(3)})] (5).
不稳定的钨腈配合物[(Cp*)W(CO)(2)(NCMe)Me]（Cp*=η(5)-C(5)Me(5)）与 H(3)SiC(SiMe(3))(3)反应得到氢化物（氢亚硅基）配合物[(Cp*)(CO)(2)(H)W=Si(H){C(SiMe(3))(3)}]（1a）。类似的反应与 H(2)SiMes(2)反应得到氢化物（亚硅基）配合物[(η(5)-C(5)Me(4)Et)(CO)(2)(H)W=SiMes(2)]（2）（Mes=2,4,6-Me-C(6)H(2)）。这些配合物中氢化物和亚硅基配体之间存在强烈的互配体相互作用；通过对[D(2)]1b 的中子衍射研究证实了这一点，即 1a 的氘代和 η(5)-C(5)Me(4)Et 衍生物。在氘代配合物[D]1a 中观察到 W-H 和 Si-D 基团之间的交换。这种 H/D 交换在室温下缓慢进行，但在紫外照射下非常迅速。变温 NMR 光谱测量显示了 1a 中羰基配体的动态行为。配合物 1a 在室温下与丙酮反应主要得到氢硅烷化产物[(Cp*)(CO)(2)(H)W=Si(OiPr){C(SiMe(3))(3)}]（3a），以及硅氧配合物[(Cp*)(CO)(2)WO(Si(H)iPr{C(SiMe(3))(3)})]（4a）。在低温下，进行了不同的反应，即 α-H 抽取，得到 1a 和二氢化物（亚硅基）配合物的平衡混合物[(Cp*)(CO)(2)(H)(2)W(Si(H){OC(=CH(2))Me}{C(SiMe(3))(3)})]（5）。
