通过 π 结合在 Bis ((iminoxolene) 金复合物中,调节异构化和连接物交换率
Thomas H Do1, David A Haungs1, William Y Chin1
1Department of Chemistry and Biochemistry, University of Notre Dame, 251 Nieuwland Science Hall, Notre Dame, Indiana 46556-5670, United States.
Inorganic chemistry
|July 12, 2023
概括
双 (iminoxolene) 复合体表现出不同的cis和trans同位素. 这种cis异构体表现出异常低能三重体状态和更快的化物解离,这是由立体电子效应和联体体阻碍驱动的.
科学领域:
- 有机金属化学 有机金属化学
- 摄影化学的使用.
- 无机化学 无机化学
背景情况:
- 伊复合物与伊米诺烯配体被研究,因为它们具有独特的电子和结构性质.
- 了解这些复合物的异构和反应性对于开发新的催化和光物理应用至关重要.
研究的目的:
- 为了研究 bis ((iminoxolene) 复合物的 cis 和 trans 异构体的形成,电子结构和反应性.
- 阐明控制跨cis异体化和化联体解离的因素.
主要方法:
- 合成和表征 bis ((iminoxolene) 复合物.
- 光谱分析 (UV-Vis,NMR) 和可变温度的NMR.
- 密度函数理论 (DFT) 的计算.
- 关于连接体解离和异构化的动态研究.
主要成果:
- 双 (iminoxolene) 复合物与二烯形成了动力 (跨) 和热力学 (cis) 异构体.
- cis和trans异构体的电子结构相似,其中包括以伊米诺克索林为中心的HOMO和金属-伊米诺克索林 π* LUMO.
- 这些cis异构体表现出异常低能三重体状态,原因是异常变化的伊米诺克索林二面角.
- 由于硬质阻碍和电子效应,转变异构体经历了显著更快的 (10^8倍) 酸解离.
结论:
- 立体电子效应和立体相互作用对伊米诺烯-复合物的稳定性和反应性起着至关重要的作用.
- 皮里丁解离速率的观察到的差异归因于联结体-联结体和联结体-金属相互作用.
- 该研究提供了对调整有机金属复合物的特性设计原则的见解.
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