在二甲中基本的光交换的警告故事终于解释了
Coral Hillel1, Sara Rough1, Christopher J Barrett1,2
1Department of Physics and Astronomy, York University, Toronto, ON, Canada.
Communications chemistry
|November 2, 2024
概括
由于溶剂光分解,像DCM这样的化溶剂会导致不可靠的阿佐本光开关异构化结果. 紫外线光触发质子,加速热异构并改变机制,解释了实验警告.
科学领域:
- 摄影化学的使用.
- 有机化学 有机化学
- 物理化学 物理化学
背景情况:
- 亚烯光开关在极性近极溶剂中进行异构研究.
- 通常使用的是化碳化合物,如二甲 (DCM).
- 不一致的结果困扰了这些溶剂中的亚博烯异构化研究.
研究的目的:
- 调查亚博热异构化中虚假结果的根本原因.
- 了解化溶剂在紫外线照射下所起的作用.
- 澄清DCM中热异构化的机制.
主要方法:
- 在DCM中对阿佐皮里丁光开关的紫外线照射.
- 皮里丁部分的质子化研究.
- 密度函数理论 (DFT) 的计算.
- 对热异构化速率的分析.
主要成果:
- 在DCM中对阿佐皮里丁的紫外线照射会导致溶剂光分解和质子化.
- 质子化显著加快了热异构化速率.
- 典型的单点三点旋转机制被质子化取消了.
- 虚假的结果归因于光分解生成的质子.
结论:
- 化溶剂不适合在紫外线触发的亚博异构化研究中使用.
- DCM的光分解产生了改变异构化通路的质子.
- 了解这种现象解释了实验中的不一致性和警告.
- 建议对光解学生成的质子有潜在的应用.
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