一个含有 (n → π*) 逆结合的同化物复合体,在温和条件下通过C-H键激活转化为化物/化物产物
Zachary D Brown1, Petra Vasko, James C Fettinger
1Department of Chemistry, University of California, 1 Shields Avenue, Davis, California 95616, USA.
Journal of the American Chemical Society
|February 15, 2012
概括
迪亚利基尔基米伦与三基异化物反应,形成一个易斯 adduct. 这种添加物经历C-H键激活,产生化/化物种和异布.
科学领域:
- 有机金属化学 有机金属化学
- 无机化学 无机化学
背景情况:
- 基烯是双价化合物.
- 异化物是协调化学中的多功能连接体.
研究的目的:
- 为了研究特定的二甲基聚烯和三甲基-丁异化物之间的反应.
- 为了阐明由此产生的易斯 adduct 的结合相互作用和反应性.
主要方法:
- 合成二甲基基米烯和易斯添加物.
- 光谱分析 (FT-IR) 用于研究结合.
- 密度函数理论 (DFT) 计算以确认电子结构.
主要成果:
- 一个易斯 adduct 的形成, (Ar(Me(6)))(2)GeCNBu(t).
- 观察C-N延伸频率下降,表明n → π*背接.
- DFT证实HOMO涉及Ge-C与异酸 π*轨道的结合.
- 易于激活 adduct 的 C-H 键.
结论:
- 这种二甲基聚烯与 tert-butyl isocyanide 形成了一个稳定的易斯附加物.
- 这种结合的特点是向异酸连接体的显著反向捐赠.
- 添加物是有反应性的,经历C-H键激活,形成新的物种.
相关概念视频
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Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...