在催化不对称的降解性阿尔多尔反应中,艾伦酸乙对子产生显著的联结效应
Dongbo Zhao1, Kounosuke Oisaki, Motomu Kanai
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan.
Journal of the American Chemical Society
|November 9, 2006
概括
这项研究引入了对艾伦基的催化不对称的还原性阿尔多尔反应,创造了性构建块. 不同的催化剂产生高选择性的玛-cis或α-aldol产物.
科学领域:
- 有机化学 有机化学
- 不对称的催化剂.
- 合成方法论 合成方法论
背景情况:
- 合成方法的发展对于获得奇拉分子至关重要.
- 降解性阿尔多尔反应是碳-碳键形成的强大工具.
- 艾伦酸乙对合成转化具有独特的反应性.
研究的目的:
- 为了开发一个一般的催化不对称的降解阿尔多尔反应的艾伦酸.
- 为了实现不同组成异构体 (-cis和α-aldol产物) 的选择性合成.
- 探索这些性产品作为有机合成中的多功能构建块的应用.
主要方法:
- 使用的铜酸盐 (CuOAc) 与 (R) -DTBM-SEGPHOS和PCy3用于玛-cis产品的形成.
- 使用的化铜 (CuF) 与一种新型的taniaphos联体 (L3) 复合,用于α-aldol产品的形成.
- 研究了各种芳香性,性和不和子的反应范围.
主要成果:
- 通过使用CuOAc/(R) -DTBM-SEGPHOS/PCy3.3.实现了高达99%的反选择性 (ee) 的玛-cis产物的主要形成.
- 使用CuF-Taniaphos复合物获得具有高二选择性和高达84% ee的alpha-aldol产品.
- 证明了该反应对广泛的基质的适用性.
- 将反应扩展到一种催化酶选择性基化醇反应.
结论:
- 开发了一种通用的催化系统,用于艾伦酸的非对称的还原性阿尔多尔反应.
- 通过催化剂选择证明了通过催化剂选择对构成性同位素形成的精确控制.
- 突出了在有机合成中合成的性产品的实用性.
- 建立了一个新的途径,用于 enantioselective 基化 aldol 反应.
相关概念视频
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