一般光介导的,高度异构选择性的皮皮二烯表皮化:从最容易获得到最稳定的立体异构体
Zican Shen1, Morgan M Walker1, Shuming Chen2
1Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States.
Journal of the American Chemical Society
|December 29, 2020
概括
这项研究引入了一种新的光催化和原子转移 (HAT) 方法,用于皮佩里丁的表皮化. 这种方法有效地产生了具有高选择性的更稳定的二聚体,适用于多种不同的piperidine结构.
科学领域:
- 有机化学 有机化学
- 光催化作用的光催化
- 立体选择性合成 立体选择性合成
背景情况:
- 皮皮里丁是药品和天然产品中普遍存在的异环基架.
- 皮佩里丁衍生物的立体选择性合成仍然是有机化学中的一个重大挑战.
- 开发有效的方法来获取特定的异构体对于药物发现和开发至关重要.
研究的目的:
- 开发一种新的以光为媒介的策略,用于piperidines的立体选择性表皮化.
- 建立一种联合光催化和原子转移 (HAT) 方法,以获得更稳定的二聚体.
- 探索这种新型表皮化方法的范围和局限性.
主要方法:
- 使用了联合光催化和原子转移 (HAT) 协议.
- 采用可见光辐射来调解表皮化反应.
- 研究了广泛的替代型皮佩里丁,包括N-非替代,N-基和N-基衍生物.
主要成果:
- 在多种piperidine基质的epimerization中实现了高的 diastereoselectivity.
- 在各种替代模式 (di-到四位替代) 中证明了转换的普遍性.
- 观察到二聚体选择性和异构体计算的相对稳定性之间的相关性.
结论:
- 开发的光催化HAT方法提供了一条有效的途径,以热力学优势的piperidine diastereomers.
- 该方法广泛适用于各种替代的piperidines,为合成化学家提供了有价值的工具.
- 机理学研究包括可逆性,发光灭,标签和量子产量测量,为反应途径提供了洞察力.
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