一个改进的催化剂对乙烯酸的不对称的arylation
Takayuki Hamada1, André Chieffi, Jens Ahman
1Contribution from the Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139.
Journal of the American Chemical Society
|February 14, 2002
概括
一种新型的催化剂能够在室温下实现子的酶选择性α-arylation. 这种高效的系统可以创建具有高产率和优异的反选择性的四元立体性中心,从而推进非对称的合成.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 不对称的合成方法
背景情况:
- 基的酶选择性α-arylation对于合成性分子至关重要.
- 以前的方法通常需要恶劣的条件或具有有限的范围.
研究的目的:
- 开发一种高反应性和酶选择性催化剂系统,用于子的α-arylation.
- 为了能够有效地形成四次性立体性中心.
主要方法:
- 一个新的催化剂是由二二乙烯 (Pd) 和一个重的dialkylphosphino-binaphthyl连接物制备的.
- 催化剂系统使用三氧化 (NaO(t) Bu) 作为与基化物反应的基础.
主要成果:
- 与以前的方法相比,新的催化剂系统显示出明显更高的反应性.
- 在室温下,化反应有效地进行,只使用2mol%的催化剂.
- 阿尔法--阿尔法'-受保护的环坦的结合产生了高产的产品,其反体过剩 (ee) 高达94%.
结论:
- 开发的催化剂系统代表了对酶选择性酸配合的重大进步.
- 这种方法在温和条件下提供了一条高效的途径,以获得性四元立体性立体性中心.
相关概念视频
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