一个基于阿佐的可光切换金属循环:合成,表征和超快的动力学
Raphael I Petrikat1, Justin Hornbogen2, Marcel J P Schmitt1
1Fachbereich Chemie, RPTU Kaiserslautern-Landau, Erwin-Schrödinger-Straße 52-54, 67663, Kaiserslautern, Germany.
Chemistry (Weinheim an der Bergstrasse, Germany)
|March 25, 2024
概括
研究人员使用亚博烯开发了第一个可光切换的金属有机金属循环. 这种新的复合体表现出可逆的E/Z光异构化而没有降解,模仿原型的阿佐本行为.
科学领域:
- 超分子化学 超分子化学
- 摄影化学的使用.
- 协调化学 协调化学
背景情况:
- 阿佐烯衍生物是众所周知的可光切换分子.
- 对光敏金属有机框架和金属循环的开发是一个活跃的研究领域.
- 了解复杂系统中的光异构化动态对于设计功能性材料至关重要.
研究的目的:
- 为了合成和表征一种基于亚博烯配体的新型可光切换金属循环.
- 研究溶液和气相中的金属循环的光异构化行为和动态.
- 阐明金属协调对阿索转换机制的影响.
主要方法:
- 合成含有亚博的配体3,3'-亚博 (metPA) (1) 和铜 (I) 金属环 (Cu) (1) (BF4) (2).
- 使用静态和时间分辨率的光谱方法进行表征,包括溶液中的 femtosecond UV/Vis 短暂吸收 (fs-TA).
- 在质谱离子陷中的气相过渡光解离 (τ-PD).
- 量子化学计算 量子化学计算
主要成果:
- 铜(I) 金属环[Cu2(1)2(BF4)2 (2) 已成功制备并证明了高度定量和可重现的光诱导E/Z切换,没有复杂的衰变.
- 观察到在小比秒到几比秒时间尺度中的超快速光诱导动态,与原型阿佐本行为一致.
- 气相和溶液相研究以及理论计算表明,金属协调对开关机制和电子路径的影响微不足道,这表明非合作性异构化过程.
结论:
- 合成的[Cu2(1)2(BF4)2 (2) 代表了基于阿佐的第一个可逆光开关 (3d) 金属循环.
- 金属循环表现出类似于亚博的光异构化动态,不受金属协调的影响.
- fs-TA和t-PD的组合为这些系统中的动态和解法的相互作用提供了宝贵的见解.
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