在水中发生enantio和 diastereoselective,立体特异的曼尼赫类反应
Tomoaki Hamada1, Kei Manabe, Shu Kobayashi
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Journal of the American Chemical Society
|June 24, 2004
概括
这项研究引入了一种新型的催化系统,使用化和性胺用于水中的不对称的曼尼赫式反应. 该方法实现了高产量和立体特异性,产生了syn或anti-Mannich adducts.
科学领域:
- 有机化学 有机化学
- 不对称的催化剂.
- 绿色化学 绿色化学
背景情况:
- 不对称的曼尼赫类反应对于合成性氨基酸至关重要.
- 在水性介质中开发高效和选择性的催化系统仍然是一个挑战.
- 这些反应中的立体化学控制可能很难实现.
研究的目的:
- 开发一种新型的催化系统,用于水中的不对称的曼尼赫式反应.
- 使用随时可用的催化剂实现高产量和选择性.
- 为了研究合成和反曼尼克引证的立体特异合成.
主要方法:
- 采用了化 (ZnF2) 和一种具有芳香环上的甲氧基团的性胺的组合.
- 在水环境中进行了触媒不对称的曼尼赫式反应.
- 作为基板使用的 (E) 或 (Z) 乙烯酸盐.
主要成果:
- 在曼尼赫型反应中获得了高产量和出色的选择性.
- 证明了同或反曼尼克 adducts 的立体特异性形成.
- 催化系统在水中有效,与绿色化学原则保持一致.
结论:
- 开发的催化系统提供了一种高效和选择性的途径,以在水中合曼尼希引物.
- 立体化学结果是可控制的,基于阳合体几何.
- 这种方法为现有的不对称曼尼赫反应提供了有价值的替代方案.
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If the substrate is an achiral molecule at the α-carbon, the inversion of configuration is not observed.
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