打断关联 π-σ-π 异构 实现 Z-保持不对称的 Tsuji-Trost 反应
Jiandong Liu1, Zhongkang Dong1, Wen-Bin Cao1
1New Cornerstone Science Laboratory, State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China.
Journal of the American Chemical Society
|January 8, 2025
概括
这项研究引入了一种新的方法,用于合成使用Z-retentive不对称的Tsuji-Trost反应的奇拉Z-olefins. 该策略控制异构化途径,使有价值的α-氨基酸衍生物能够有效地生产.
科学领域:
- 有机化学
- 不对称的催化
- 立体选择合成
背景情况:
- 不对称的Tsuji-Trost反应对于形成立体中心至关重要,通常由于稳定的syn-π-allylpalladium中间体产生E-olefins.
- 由于快速的π-σ-π异构化,合成Z-olefin产品具有挑战性,这有利于在热力学上更稳定的syn中间体而不是短暂的反π-allylpalladium中间体.
研究的目的:
- 在不对称的Tsuji-Trost反应中开发一种控制协会 π-σ-π 异构的策略.
- 为了能够有效地合成性Z-olefin产品,特别是α-氨基酸衍生物.
主要方法:
- 调整连接体的体质量,基离子组和对抗离子来调节异构.
- 使用来自奇拉胺联体的 (Pd) 催化剂来中断异构.
- 研究Z-保留反应途径的机制性见解.
主要成果:
- 实现了一个高效的Z-保留性不对称的Tsuji-Trost反应.
- 合成的α-氨基酸衍生物具有高产率 (高达95%) 和优异的立体选择性 (高达99%,>19:1 Z/E比率).
- 在低催化剂负荷 (0.1 mol %) 的情况下证明成功应用.
结论:
- 开发的策略有效调节π-σ-π异构,使Z-保留合成成为可能.
- 这项工作为未来Z-保留性不对称的Tsuji-Trost类反应的合理设计提供了基础.
- 该方法提供了一条有价值的途径,以获得具有Z-olefin部分的复杂α-氨基酸衍生物.
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