甲索基替代的α,n-二甲基酸.甲索基替代的α,n-二甲酸. 光化学生成和极极与二极极极的反应性
Carlotta Raviola1, Davide Ravelli, Stefano Protti
1Photogreen Lab, Department of Chemistry, University of Pavia , V. Le Taramelli 12, 27100 Pavia, Italy.
Journal of the American Chemical Society
|September 9, 2014
概括
研究甲) 三甲基西兰的光反应性揭示了不同的化学路径. 不同的替代导致酒精中的基因或离子化学,这取决于甲氧基组.
科学领域:
- 有机化学 有机化学
- 摄影化学的使用.
- 计算化学的计算化学
背景情况:
- 了解有机纤维素的光反应性对于开发新的合成方法至关重要.
- 在光化学条件下替代基基烯的行为尚未完全阐明.
- 甲基替代剂可以显著影响反应通路.
研究的目的:
- 在酒精溶剂中研究各种替代 (甲) 三甲基西兰的光反应性.
- 阐明反应机制,区分激素和离子通路.
- 为了探索甲基组位置对光活性的影响.
主要方法:
- 结合实验和计算 (量子化学) 的研究.
- 在甲醇和甲醇/水混合物中的光化学反应.
- 对脱离速率和竞争反应的动态分析.
主要成果:
- 光反应通过消除化物和三甲基基离子进行,形成甲基替代的α,n-二甲基烯 (α,n-MeO-DHTs).
- 测量了脱速率,与酸脱速率大约在 10^8 s^-1.1 的情况下竞争.
- α,2-MeO-DHT和α,4-MeO-DHT表现出极端行为 (从甲醇中提取H).
- α,3-MeO-DHT主要表现出离子化学,这归因于脱过程中的三重单重表面交叉.
结论:
- 甲基替代剂的位置决定了光反应路径 (根基与离子).
- 三重-单重表面交叉在α,3-MeO-DHT的离子化学中发挥着关键作用.
- 这项研究提供了关于在光化学条件下被替代的有机素的结构-反应关系的见解.
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