立体分离的Zweifel化及其机械二分论
Samir Manna1, Swagata Paul1, Wang-Yeuk Kong2
1Department of Chemistry, Indian Institute of Technology, Kharagpur, West Bengal, India.
Angewandte Chemie (International ed. in English)
|July 26, 2023
概括
这项研究引入了一种立体选择性的Zweifel化方法,用于合成乙烯基异烯和合二烯. 它实现了前所未有的对E与Z选择性的控制,提供了新的合成途径.
科学领域:
- 有机化学 有机化学
- 合成方法论 合成方法论
- 立体选择性合成 立体选择性合成
背景情况:
- 兹韦菲尔化是有机合成中的一个关键反应.
- 在使用具有多个反应性π系统的酸盐复合物时,控制立体选择性存在挑战.
- 在此类系统中选择性激活烯酸仍未被探索.
研究的目的:
- 开发一种立体选择性的Zweifel烯化,用于合成乙烯基异质和合的1,3-二烯.
- 为了在这些合成中获得高产量和高达100%的立体选择性.
- 探索前所未有的E与Z-乙烯基异构的形成,并研究立体选择性逆转.
主要方法:
- 用了两个不同的反应型π-系统的酸盐复合物,用于Zweifel炼.
- 使用密度函数理论 (DFT) 调查以阐明反应机制.
- 研究了2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) 作为电爱好者的作用,以诱导立体选择性逆转.
主要成果:
- 实现了对乙烯基异构和合1,3-烯的立体选择性合成,产量好,立体选择性高.
- 报告了在相同条件下对E与Z-维尼尔异烯形成的前所未有的控制.
- 通过使用DDQ证明了一种新的立体选择性逆转,并解决了选择性烯激活的挑战.
结论:
- 开发的Zweifel精制法为可贵有机化合物的立体选择性合成提供了一个强大的工具.
- 来自DFT的机械洞察力解释了导致E或Z异构体的二分法.
- 这项工作为合成具有精确立体化学控制的复杂分子开辟了新的途径.
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