Department of Chemistry, Columbia University , New York, New York 10027, United States.
J Am Chem Soc. 2014 Dec 31;136(52):17934-7. doi: 10.1021/ja510703s. Epub 2014 Dec 17.
W(PMe3)4(η(2)-CH2PMe2)H reacts with PhSiH3 to give the first examples of diphenyldisilanyl compounds, W(PMe3)4(SiH2SiHPh2)H3 and W(PMe3)3(SiH2Ph)(SiH2SiHPh2)H4, via a mechanism that is proposed to involve migration of a SiHPh2 group to a silylene ligand. In addition to the formation of the aforementioned mononuclear compounds, the reaction of W(PMe3)4(η(2)-CH2PMe2)H with PhSiH3 also yields a novel dinuclear compound, W(PMe3)2(SiHPh2)H2(μ-SiH2)[W(PMe3)3H2], which features a bridging silylene ligand that participates in 3-center-2-electron interactions with both tungsten centers. The bonding within the [W(μ-H)Si(μ-H)W] core can be described by a variety of resonance structures, some of which possess multiple bond character between tungsten and silicon. In this regard, W(PMe3)2(SiHPh2)H2(μ-SiH2)[W(PMe3)3H2] possesses the shortest W-Si bond length reported. The corresponding reaction of W(PMe3)4(η(2)-CH2PMe2)H with Ph2SiH2 yields the σ-silane compound, W(PMe3)3(σ-HSiHPh2)H4.
W(PMe3)4(η(2)-CH2PMe2)H 与 PhSiH3 反应，通过一种被认为涉及 SiHPh2 基团迁移到硅烯配体的机制，生成了第一个二苯二硅基化合物 W(PMe3)4(SiH2SiHPh2)H3 和 W(PMe3)3(SiH2Ph)(SiH2SiHPh2)H4。除了形成上述单核化合物外，W(PMe3)4(η(2)-CH2PMe2)H 与 PhSiH3 的反应还生成了一种新型双核化合物 W(PMe3)2(SiHPh2)H2(μ-SiH2)[W(PMe3)3H2]，其特征在于桥联硅烯配体与两个钨中心参与 3 中心 2 电子相互作用。[W(μ-H)Si(μ-H)W] 核内的键合可以用各种共振结构来描述，其中一些结构在钨和硅之间具有多重键特征。在这方面，W(PMe3)2(SiHPh2)H2(μ-SiH2)[W(PMe3)3H2] 具有报道的最短 W-Si 键长。W(PMe3)4(η(2)-CH2PMe2)H 与 Ph2SiH2 的相应反应生成了 σ-硅烷化合物 W(PMe3)3(σ-HSiHPh2)H4。
