(I2) 在有机金属学中作为Janus面联体
Andrey Yu Rogachev1, Roald Hoffmann
1Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA.
Journal of the American Chemical Society
|February 7, 2013
概括
二氧化 (I2) 复合体呈现出不同的几何形状,这取决于I2 是否作为电子受体或电子供体. 使用自然键轨道 (NBO) 方法分析的这种结合行为解释了这些金属复合物的结构多样性.
科学领域:
- 无机化学 无机化学 有机化学
- 计算化学计算化学
- 材料科学 材料科学 材料科学
背景情况:
- (I2) 复合体表现出不同的几何形状.
- I2作为电子捐赠者或接受者的作用影响了复杂的结构.
- 了解这些相互作用是设计新型金属复合物的关键.
研究的目的:
- 阐明控制二复合物的结合原理.
- 为了区分I2作为电子受体与电子供体之间的作用.
- 解释已知的I2复合体中观察到的结构变异.
主要方法:
- 在自然键轨道 (NBO) 框架内的扰动理论.
- 能量分解分析 (EDA).
- 对正规分子轨道 (MO) 和NBO进行比较分析.
主要成果:
- 在范科复合体中充当受体,其结合涉及 σ*(I-I) 和金属 d(z) 2 轨道.
- 在棉花,迪卡列夫和彼得鲁希纳综合体中充当了捐赠者,其中包括从I2单一对捐赠到金属σ*(Rh-Rh) 反结合轨道.
- 模型计算证实了d(8) 复合体和I2 供体能力的结合特性.
结论:
- I2复合体的几何多样性直接来自其接受者或捐赠者的作用.
- NBO分析为了解这些相互作用提供了一个强大的框架.
- 获得的洞察力可以指导新I2含有金属复合物的合成.
相关概念视频
Properties of Organometallic Compounds
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Structural Isomerism
Isomerism in Complexes
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.
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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...
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Stereoisomerism
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
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Arenediazonium substitution reactions occur when the diazonium group is substituted by various functional groups such as halides, hydroxyl, nitrile, etc. For instance, arenediazonium salts react with copper(I) salts of chloride, bromide, or cyanide to form corresponding aryl chlorides, bromides, and nitriles. These reactions are named Sandmeyer reactions. Although the mechanism of this reaction is complicated, as illustrated in Figure 1, they are believed to progress via an aryl copper...


