Fe/Ru/Os-bis(arene) 复合体的环滑和多电子氧化还原特性:触觉性变化真的会导致潜在反转吗?
Richard L Lord1, Cynthia K Schauer, Franklin A Schultz
1Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States.
Journal of the American Chemical Society
|September 8, 2011
概括
八组金属的双甲复合物表现出不同的电子转移机制. 由结合驱动的触觉性变化控制了这些过渡金属化合物中明显的多电子行为.
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
- 电化学 电化学 电化学
背景情况:
- 第8组 bis ((hexamethylbenzene) 金属复合物 (Fe,Ru,Os) 呈现出不同的氧化还原行为.
- 电子转移机制和热力学在M(II) →M(I) →M(0) 系列中存在显著差异.
- 以前的猜测将Fe(0) 的触觉性与连续的电子转移联系在一起.
研究的目的:
- 为了研究8组bis ((hexamethylbenzene) 复合物的电子转移机制.
- 阐明触觉性变化在控制氧化还原行为的作用.
- 开发一个概念模型来理解d(6) bis((arene) 氧化还原化学.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 已建立的模型化学被利用.
- 进行了电化学实验.
主要成果:
- Fe复合体显示了不同的氧化还原电位; Ru显示重叠的电位; Os显示了两个电子的转移.
- 触觉性变化是结合的结果,影响电子附着.
- 青的Fe(0) 状态是三倍的 η(6):η(6),而不是建议的 η(4):η(6).
- 根据触觉性变化发生的时间,Ru和Os使用不同的机制.
结论:
- 触觉性变化本身并不能保证多电子的行为.
- 垂直电子附着决定了明显的多电子氧化还原事件.
- 建立了d(6) bis(arene) 氧化还原行为的一般模型,适用于Fe三位一体之外.
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