三坐标的Ni (III) - imide复合物的合成和特征
Vlad M Iluc1, Alexander J M Miller, John S Anderson
1Gordon Center for Integrative Science, Department of Chemistry, University of Chicago, Chicago, Illinois 60637, USA.
Journal of the American Chemical Society
|July 30, 2011
概括
研究人员合成了新的 (III) - 胺基,探索了它们的电子和磁性特性. 立体质量和电子因素,特别是2,6-dimesitylphenyl组,对于稳定这些低坐标复合体至关重要.
科学领域:
- 有机金属化学 有机金属化学
- 无机化学 无机化学 有机化学
- 材料科学 材料科学 材料科学
背景情况:
- 低坐标复合物由于其独特的反应性和电子结构而引起人们的兴趣.
- 在胺中稳定较高的氧化状态对合成提出了挑战.
- 对于催化应用来说,了解电子和固态对胺稳定性的影响至关重要.
研究的目的:
- 合成和描述一个新的低坐标像体家族.
- 研究 (III) - 胺基与和替代物的电子和磁性特性.
- 阐明硬质体在稳定-核心中的作用.
主要方法:
- 由1,2-bis(di-tert-butylphosphino) 乙支持的 (II) 前体的合成.
- 氧化 (II) 复合物,形成 (III) - 胺基.
- 和替代 (III) 胺基的隔离和完整的特征.
- 可变温度磁性测量和电子磁共振 (EPR) 谱学.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 成功合成和表征和替代的 (III) - 胺基.
- 2,6-dimesitylphenyl替代剂显著稳定了Ni (III) - imide部分.
- 可变温度的磁性研究显示了和替代复合物的不同性质,表明衍生物的自旋状态平衡.
- DFT计算证实了未配对电子的定位在imide上,并突出了原子抽象中亚达曼替代物的反应性.
- 2,6-dimesitylphenyl组的立体效应被证明可以保护NiN核心并影响分子构造.
结论:
- 已经建立了一个新的低坐标胺基家族,为的更高氧化状态提供了洞察力.
- 2,6-dimesitylphenyl组的固体质量对于稳定反应性 (III) 胺物种至关重要.
- DFT计算为电子结构,自旋状态和反应性,特别是原子抽象提供了宝贵的机械洞察力.
相关概念视频
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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.
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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