通过动态运动分辨率进行QUINAP的不对称合成
Vikram Bhat1, Su Wang, Brian M Stoltz
1Caltech Center for Catalysis and Chemical Synthesis, Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California, 91125, United States.
Journal of the American Chemical Society
|October 25, 2013
概括
一种新的催化方法使得具有高选择性的重要QUINAP配体和衍生物的不对称合成成为可能. 这种高效的工艺利用了较低的催化剂负荷,并提供了直接通往这些有价值的性素连接体的途径.
科学领域:
- 有机金属化学 有机金属化学
- 不对称的催化剂.
- 连接物合成 连接物合成
背景情况:
- 化胺联体,如QUINAP,在不对称合成中至关重要,用于生产化纯化合物.
- 开发高效和选择性的合成这些配体的方法对于促进催化应用至关重要.
- 以前的方法可能受到产量,选择性或催化剂效率的限制.
研究的目的:
- 为QUINAP及其衍生物的不对称合成开发一种选性C-P合过程.
- 为了探索各种离开组 (化物,三酸盐,OSs) 的催化合反应.
- 使用低催化剂负载实现高反体过剩和产量.
主要方法:
- 由催化的CP合反应.
- 不同前体的选:化物,三酸盐 (OTf) 和4-甲硫尼尔二硫酸盐 (OSs).
- 反应条件的优化,以实现异型选择性和高产量.
主要成果:
- 成功合成QUINAP及其衍生物的不对称合成,具有高反体过剩.
- 鉴定了三叶酸作为一种前体,通过烯中间体异构化导致一种新的动态动力学分辨率.
- 使用低催化剂负载 (≤3 mol % Pd) 实现良好的高产率和选择性.
结论:
- 为了QUINAP合成,已经建立了一种新且操作上简单的催化选择性CP合方法.
- 开发的方法提供了有效的获取有价值的性素连接体,具有优异的酶选择性.
- 这些发现有助于通过改进的连接物合成策略来推进非对称催化.
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