不对称的光化学 [2 + 2] - 循环添加亚环维尼尔皮里丁通过三级复合物形成和不受控制的敏感化机制
Zebediah C Girvin1, Laura F Cotter1, Hyung Yoon1
1Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut06511, United States.
Journal of the American Chemical Society
|October 20, 2022
概括
在三重能量转移光化学反应中实现立体化学控制是具有挑战性的. 本研究提出了一种使用光催化剂的新策略,通过有组织的过渡状态来实现 [2 + 2] 光环添加的高选择性.
科学领域:
- 摄影化学
- 有机合成
- 催化剂
背景情况:
- 在三重能量转移光化学反应中的立体化学控制是一个持续的挑战.
- 高度反应的开中间体往往导致立体随机反应.
- 目前的策略集中在形成基态性复合体以直接反应.
研究的目的:
- 开发一种新的立体选择性光化学 [2 + 2] 光环添加的策略.
- 通过使用独特的机理范式,实现高 stereoselectivity 和 enantioselectivity.
- 证明控制涉及自由基质和催化剂相关元件的反应.
主要方法:
- 使用 (III) 光催化剂进行三重能量转移.
- 使用合催化剂相关的乙烯和自由乙烯基底.
- 调查一个优选的,高度组织的过渡状态的形成.
主要成果:
- 在 [2 + 2] 光环添加中实现了高水平的二元选择性和反选择性.
- 尽管存在非催化剂途径,但该策略成功控制了立体化学.
- 一个不同的机械主义范式,不同于当前的方法,被阐明.
结论:
- 通过三重能量转移建立了立体选择性光化学反应的新策略.
- 这些发现为光化学中的现有立体控制方法提供了补充方法.
- 这项工作促进了对光催化过程中通过有组织的过渡状态来控制反应的理解.
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