在具有MII,P,P2+ (M = Pd,Pt) 架构的复合体上,协调性亚联体之间没有切换合作性
Ot Raïch Panisello1, Jesús Jover1,2, Cristina Puigjaner3
1Secció de Química Inorgànica, Departament de Química Inorgànica i Orgànica, Universitat de Barcelona, Martí i Franquès 1-11, 08028 Barcelona, Spain.
Inorganic chemistry
|August 21, 2024
概括
新的和化合物与阿佐烯配体表现出光化学活性. 它们的cis-to-trans异构化机制涉及旋转,而不是连接体合作性,正如DFT计算所证实的那样.
科学领域:
- 协调化学 协调化学
- 摄影化学的使用.
- 有机金属化学 有机金属化学
背景情况:
- 亚二联体因其光异构化特性而闻名.
- 方形平面金属复合体为研究连接体行为提供了一个平台.
- 了解异构化机制对于设计光响应材料至关重要.
研究的目的:
- 用亚博烯配体合成和表征新的和复合物.
- 为了研究这些复杂物体的光化学转化-至-cis异体化.
- 阐明 cis-to-trans 热反反应的机制.
主要方法:
- 合成和全面描述正方形平面的和化合物.
- 图形化学研究的转向cis异体化.
- 在不同条件下 (溶剂,温度,压力) 的cis-to-trans热反应的动力学研究.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 成功合成和表征了[M2pppp][azo]2][OTf]2和[M2tpbz][azo]4][OTf]4复合体.
- 复合体表现出光化学的转化至cis异体化,类似于自由联结体.
- 动力学研究揭示了 cis-to-trans 反应的旋转机制.
- 在相同的金属中心上,在亚博烯配体之间没有观察到合作性.
- DFT计算支持了关于光异构体能量的实验发现.
结论:
- 合成的和酸复合物具有光化学活性.
- cis-to-trans 异体化通过旋转机制进行,没有连接体合作.
- DFT计算为理解观察到的光化学行为提供了一个理论框架.
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