Reactions of Isocyanides with Metal Carbyne Complexes: Isolation and Characterization of Metallacyclopropenimine Intermediates
Reactions of Isocyanides with Metal Carbyne Complexes: Isolation and Characterization of Metallacyclopropenimine Intermediates
复制标题
异氰化物与金属碳炔配合物的反应：金属环丙烯亚胺中间体的分离和表征。
DOI：
10.1021/jacs.6b13275
复制
发表时间：
2017-02-08
影响因子：
15
通讯作者：
Xia, Haiping
中科院分区：
文献类型：
--
作者：
Luo, Ming;Long, Lipeng;Xia, Haiping
η（2）-亚氨基烯酮类物质通常被假定为亲核试剂诱导的碳炔-异氰化物C-C偶联过程中的中间体。然而，这样的物种是难以捉摸的。在这里，我们报告的直接形成eta（2）-亚氨基烯酮配合物的反应，金属戊炔异腈。我们的研究表明，异腈的N-取代基的空间位阻效应对η（2）-亚氨基烯酮配合物的三元金属杂环的稳定性起着重要的作用。空间体积大的异腈，例如叔丁基或1-金刚烷基异腈，抑制异腈氮原子处的弯曲，这是形成η（2）-亚氨基烯酮基结构的要求。金属戊炔与过量异氰化物的反应允许金属桥连的金属茚衍生物由于异氰化物插入金属戊炔的M-C-α-σ键而被分离。
eta(2)-Iminoketenyl species have often been postulated as the intermediates in nucleophile-induced carbyne-isocyanide C-C coupling processes. However, such species are elusive. Here we report direct formation of eta(2)-iminoketenyl complexes from reactions of metallapentalyne with isocyanides. Our studies show that steric effects of N-substituents of the isocyanides play an important role in the stability of the three-membered metallacycles of the eta(2)-iminoketenyl complexes. Sterically bulky isocyanides, such as tert-butyl or 1-adamantyl isocyanides, inhibit bending at the isocyanide nitrogen atoms, a requirement for formation of eta(2)-iminoketenyl structures. Reactions of metallapentalyne with excess isocyanide allow the metal-bridged metallaindene derivativesto be isolated as a result of the isocyanide insertion into the M-C-alpha sigma bond of metallapentalyne.