一个实验性的立体选择性光化学 [1s,3s] - 西格马特罗普移和西格马特罗普/状交叉点的存在
Niels Hammer1, Mette Louise Christensen1, Yu Chen2
1Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark.
Journal of the American Chemical Society
|March 20, 2020
概括
研究人员发现了第一个光化学立体选择性[1,3]-转移. 这种由有机催化开始的反应通过形交叉机制产生具有高立体选择性的基产物.
科学领域:
- 有机化学
- 摄影化学
- 有机催化剂
- 计算化学
背景情况:
- [1,3] - 符号转移是基本的有机反应.
- 立体选择合成对于开发复杂分子至关重要.
- 光化学反应为化学转化提供了独特的途径.
研究的目的:
- 报告第一个光化学选择性[1,3]-sigmatropic silyl转移的实验发现.
- 使用计算方法阐明这种前所未有的光反应的机制.
- 证明圆交叉在选择性光化学中的作用.
主要方法:
- 有机催化酶选择性级联注销以合成三甲基-o-异反应剂.
- 光化学 [1,3]-转移反应
- 实验研究包括对等分子比率 (e.r. ) 的情况.
- 使用CASSCF,DFT和TD-DFT计算的计算调查.
主要成果:
- 一个有 >99:1 e.r. 的三甲基-o-异反应物的成功合成
- 观测一种立体选择性的光化学[1,3]-转移,产生一种基产物,其时效率为96:4.
- 反应机制的阐释,提出单个基/基圆交叉路径.
结论:
- 这项研究报告了第一个光化学立体选择性[1,3]-转移的艾利西兰.
- 反应以高立体选择性进行,由形交叉驱动.
- 这项研究强调了形交叉在控制光化学选择性的重要作用.
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