印尼尔-复合物的连续单电子氧化还原反应中的逐步触觉性变化:结合电化学,ESR,X射线和理论研究
M E Stoll1, P Belanzoni, M J Calhorda
1Department of Chemistry, University of Vermont, Cook Physical Science Building, Burlington, Vermont 05405-0125, USA.
Journal of the American Chemical Society
|October 25, 2001
概括
这项研究揭示了含有内连接体的复合体经历了阶段性电子转移,涉及到内环结构和结合的显著变化. 这些发现为有机金属化学中的电子转移机制提供了洞察力.
科学领域:
- 有机金属化学 有机金属化学
- 电化学 电化学 电化学
- 频谱学是一种光谱学.
背景情况:
- 研究了有内联体的复合体的电化学行为.
- 专注于减少中性复合物的二和氧化.
研究的目的:
- 为了阐明一电子转移在-内复合体中的机制.
- 描述与电子转移相关的结构和电子变化.
- 为了确定氧化还原过程的热力学和动力学.
主要方法:
- 进行X射线衍射研究以确定复杂结构.
- 循环电压测量和批量电解用于电化学分析.
- 电子自旋共振 (ESR) 谱学用于研究中间激素.
- 密度函数理论 (DFT) 和扩展赫克尔 (EH) 计算用于分子轨道分析.
主要成果:
- 一个电子的逐步减少/氧化通过一个中间基 (1+) 发生.
- 在电子转移时观察到的内环扭曲 (滑动折叠角Omega) 的显著变化.
- 在ESR光谱中,来自内环的H2质子的大型超细分离.
- 电化学数据表明有利的电子转移动力学与最小的内部球体重组能量.
结论:
- 基质中间体中的金属-内结合是在eta5和eta3触觉之间.
- 大规模的超细分离是由于内球轨道和SOMO两者都对内基-H2的极化造成的.
- 逐步的电子转移允许显著的结构变化 (eta5/eta3触觉转移) 具有低的重组能量.
相关概念视频
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Selection Rules: Photochemical Activation
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