Synthesis and structure of a hydrido(hydrosilylene)ruthenium complex and its reactions with nitriles.
Synthesis and structure of a hydrido(hydrosilylene)ruthenium complex and its reactions with nitriles.
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DOI：
10.1002/anie.200703154
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发表时间：
2007-11
影响因子：
--
通讯作者：
M. Ochiai;H. Hashimoto;H. Tobita
中科院分区：
文献类型：
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作者：
M. Ochiai;H. Hashimoto;H. Tobita
过渡金属硅烯配合物是有机硅化合物各种转化反应的关键中间体，在过去的二十年里引起了人们的广泛关注。[1]已经制备了许多亚甲硅烷基络合物，并研究了它们的反应性，但是亚甲硅烷基络合物与底物的明确反应受到限制，因为亚甲硅烷基配体上的两个大体积基团（这是稳定亚甲硅烷基络合物所必需的）仅允许非常小的底物分子进入反应性亚甲硅烷基硅位点。最近，蒂利等。[2]和我们的小组[3]已经成功地合成了在亚甲硅烷基配体上具有氢原子的亚甲硅烷基络合物，并且证明了这些络合物甚至可以与正常尺寸的底物分子如酮、环氧乙烷和腈干净地反应。这些结果表明，具有更小位阻和更高反应活性的SiO2-H键的硅烯基配合物可以发展成为硅烯基配合物化学的一个新的丰富领域。本文报道了第一个中性双（硅氢亚基）钌配合物[Cp*（CO）（H）Ru= Si（H）{C（SiMe 3）3}]（1，Cp*= C5 Me 5）的合成、1的结构表征以及该配合物通过与η2-SiMeH配位的Agostic配合物的中间体形成而活化腈的C2C键。本文报道了一种钨双（氢化硅烯）配合物[Cp*（CO）2（H）W= Si（H）{C（SiMe 3）3}]（2）的合成。[3a]因此，将类似的方法应用于钌类似物1的合成：在约58 ℃下用UV光照射[Cp* Ru（CO）2 Me]和H3 SiC（SiMe 3）3的C6 D 6溶液。然而，代替1，形成甲硅烷基络合物[Cp*（CO）2 Ru {SiH 2C（SiMe 3）3}]（3），如通过NMR光谱测定的，产率为76%。通过除去CO将3转化为1是不成功的，即使在重复的辐照-脱气循环中也是如此。
Transition-metal–silylene complexes have attracted much attention during the last two decades, as they are considered key intermediates in various transformation reactions of organosilicon compounds.[1] Numerous silylene complexes have been prepared and their reactivities investigated, but clear-cut reactions of silylene complexes with substrates have been limited, because two bulky groups on the silylene ligand, which have been necessary to stabilize the silylene complexes, only allowed access of very small substrate molecules to the reactive silylene silicon site. Recently, Tilley et al.[2] and our group [3] have succeeded in synthesizing the silylene complexes having a hydrogen atom on the silylene ligand, and demonstrated that these complexes can react cleanly even with normal-sized substrate molecules such as ketones, oxiranes, and nitriles. These results imply that silylene complexes having a less sterically hindered and more reactive SiÀH bond on the silylene ligand could develop into a new rich field in the chemistry of silylene complexes. Herein we report the synthesis of the first neutral hydrido (hydrosilylene) ruthenium complex [Cp*(CO)(H) Ru= Si (H){C (SiMe3) 3}](1, Cp*= C5Me5) utilizing a new synthetic approach, the full structural characterization of 1, and CÀC bond activation of nitriles by this complex through intermediate formation of an agostic complex with η2-SiÀH coordination. We reported the synthesis of a tungsten hydrido (hydrosilylene) complex [Cp*(CO) 2 (H) W= Si (H){C (SiMe3) 3}](2) by a photoreaction.[3a] Thus, a similar method was applied for the synthesis of the ruthenium analogue 1: a C6D6 solution of [Cp* Ru (CO) 2Me] and H3SiC (SiMe3) 3 was irradiated with UV light at about 58C. However, instead of 1, silyl complex [Cp*(CO) 2Ru {SiH2C (SiMe3) 3}](3) formed in 76% yield as determined by NMR spectroscopy. Conversion of 3 into 1 by removal of CO was unsuccessful even on repeated irradiation–degassing cycles.