在[CpOsH4(L) ]+ (L = PPh3,AsPh3和PCy3) 中对分子二激活的电子和固体效应
Charles Edwin Webster1, Christopher L Gross, Dianna M Young
1Department of Chemistry, Texas A&M University, College Station, Texas 77842-3012, USA.
Journal of the American Chemical Society
|October 27, 2005
概括
二复合体表现出独特的"延长"H2配体,其方向和键长度受到固体和电子因素的影响. 这些发现揭示了关于二联体在有机金属化学中的行为的关键见解.
科学领域:
- 有机金属化学 有机金属化学
- 无机化学 无机化学
- 计算化学计算化学
背景情况:
- 研究过渡金属复合体中二联体的性质对于理解它们的反应性和结合性至关重要.
- 与二联体 ([Cp*OsH(4)(L)][BF(4)) 的奥斯复合体为研究这些相互作用提供了一个独特的平台.
研究的目的:
- 通过实验和理论分析与结合的,长长的二连接体的结构和动态.
- 确定易斯基联体 (L) 的性质如何影响二联体的方向,键长和旋转屏障.
主要方法:
- 单晶中子衍射用于结构确定.
- 无弹性中子散射用于分析旋转动力学.
- 密度函数计算用于电子和固态效应的理论建模.
主要成果:
- 二联体的H-H键长度和方向与易斯基联体 (L) 有显著差异.
- L 的立体和电子因子决定了分子几何形状,影响了 Os 5d 轨道能量和 H-H 相互作用.
- 对二联体的实验和计算的旋转障碍显示出很好的一致性.
结论:
- 与结合的二联体的结构和动态对辅助联体的电子和硬质性质敏感.
- 计算方法准确地预测观察到的结构和动态特性,验证理论模型.
- 这些发现提供了对有机金属复合体中二联体行为的更深入的理解.
相关概念视频
Hybridization of Atomic Orbitals II
sp3d and sp3d 2 Hybridization
Carboxylic Acids to Acid Chlorides
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Photochemical Electrocyclic Reactions: Stereochemistry
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
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