非对称双金属催化启用基Z/E相互异构
Guanlin Li1, Ziyun Lai1, En Zheng2
1Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, State Key Laboratory of Synergistic Chem-Bio Synthesis, Frontiers Science Center for Transformative Molecules, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China.
Journal of the American Chemical Society
|June 5, 2025
概括
这项研究引入了一种新的Pd/Cu催化方法,用于双向Z/E异构化烯酸,从而实现性氨基酸衍生物的立体定义合成. 这种可扩展的工艺可以实现高产量和对有价值的基化合物的反选择性.
科学领域:
- 有机化学
- 催化剂
- 立体化学
背景情况:
- 烯是CC键几何学决定分子性质的关键功能组.
- 可控制的双向基几何异构化 (Z/E) 对于立体定义合成至关重要,但仍然具有挑战性.
- 现有的方法往往缺乏对Z/E转换的控制,限制了对特定的烯异构体的获取.
研究的目的:
- 开发一种可控的双向Z/E异构化基组的新型催化系统.
- 合成具有定义的Z-和E-基基组的奇拉非天然氨基酸衍生物.
- 在异构和合成过程中实现高产量,Z/E选择性和反选择性.
主要方法:
- 使用 (Pd) /铜 (Cu) 双金属催化系统进行Z/E相互异构.
- 采用Pd介导的π-σ-π相互转换,然后用化Cu催化剂产生的N-甲化亚化进行捕获.
- 进行计算研究以了解双金属系统的机制和选择性.
主要成果:
- 实现了高产率 (高达92%) 和优良的选择性 (>20:1 Z/E或E/Z) 的基基相互异构.
- 合成的性非天然氨基酸衍生物具有高反度 (>99% ee) 以反和Z/E分离的方式.
- 证明了产品在合成有价值分子中的可扩展性,并证实了产品的有用性.
结论:
- Pd/Cu催化系统提供了一种强大而高效的双向Z/E烯异构化方法.
- 这种方法可以从Z/E混合物中合成含有Z-或E-基基的有价值的性分子.
- 与单金属系统相比,双金属催化提供了优越的立体同位素区分,从而产生了特殊的选择性.
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