在非对称的基化过程中,协调原氨基/协同催化
Yaning Wang1,2, Junli Chai3, Chang You4
1Key Laboratory for Molecular Recognition and Function , Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190 , China.
Journal of the American Chemical Society
|January 18, 2020
概括
一种新型的性初级氨基作为双催化剂和配体,使得催化不对称的基化. 这种方法有效地产生具有高选择性的复杂分子,从而提供对两种反体的访问.
科学领域:
- 有机化学
- 催化剂
- 不对称的合成
背景情况:
- 原胺是有机合成中的多功能催化剂和配体.
- 催化不对称的基化是形成碳-碳键的关键方法.
- 开发控制立体化学和反应速率的催化剂对于高效的合成至关重要.
研究的目的:
- 开发一种新型的含有甲基的原氨基作为双氨基催化剂和配体.
- 研究其与的协同催化,以进行不对称的基化.
- 在创建非循环全碳四元立体中心方面实现高效率和选择性.
主要方法:
- 使用含有甲基的性初级氨基作为双催化剂和配体.
- 采用协同催化方法对α分支β-基的不对称基化.
- 进行机制研究以阐明催化途径和协调模式.
主要成果:
- 与其体积较大的衍生物相比,含有甲基的原氨酸显示出增强的反应速率和逆转的原诱导.
- 在全碳四元立体中心的形成中实现了高效率和优异的区域,立体和反选择性.
- 使用相同配置的性氨基催化剂可以获取产品的两种酶体.
- 一个独特的Pd-arene π-协调模式被确定为有效催化剂的关键.
结论:
- 开发的π-协调性性初级胺是一种有效的双催化剂和对象对不对称的基化.
- 这种方法提供了对立体化学的控制以获得有价值的性构建块.
- 催化剂在涉及各种基质的不对称结合反应中具有广泛的适用性.
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