可调节的不对称催化通过接体堆叠在合刚性棒中
Matthieu Raynal1, François Portier, Piet W N M van Leeuwen
1UPMC Univ Paris 06 , UMR 7610, Chimie des Polymères, F-75005 Paris, France.
Journal of the American Chemical Society
|October 25, 2013
概括
基拉尔-1,3,5-三胺 (BTA) 连接物自组装成螺旋聚合物,使催化化过程中具有很高的反选择性. 混合不同的BTA单体进一步增强了这种催化性性转移.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 超分子化学 超分子化学
背景情况:
- 基拉尔配体对于不对称的催化作用至关重要.
- 在催化剂中实现高的enantioselectivity,在这种催化剂中,奇拉中心远离金属中心仍然是一个挑战.
- 自组装为构建性催化环境提供了一种新的方法.
研究的目的:
- 为了研究在催化不对称化中使用奇拉-1,3,5-三胺 (BTA) 连接体.
- 探索自我组装和聚合物形成在诱导酶选择性中的作用.
- 为了证明在催化过程中将士和士兵原则的应用.
主要方法:
- 合成带有远程性侧链的性二-1,3,5-三胺 (BTA) 连接体.
- 用催化二甲基伊他康酸的不对称化.
- 控制实验和光谱分析以阐明机制.
- 涉及不同BTA单体的共聚化研究.
主要成果:
- 在使用性BTA连接体的不对称化过程中,可以达到高达82%的反体过量 (ee).
- 谱学研究证实了通过BTA单体的自我结合形成合螺旋聚合物.
- 添加一种无氨酸的利BTA共体,增加了对88%的enantioselectivity ee.
- 一种阿基拉BTA连接体表现出31% ee,突出显示了自组装单元之间的催化相关的性转移.
结论:
- 嵌合体BTA连接体可以形成自组合的螺旋型聚合物,作为不对称催化剂的有效嵌合体环境.
- 酵素选择性是由超分子组织驱动的,而不是直接的协调.
- 混合不同的BTA单体是一种简单的策略,可以提高催化性能.
- 这项工作例证了非对称催化中的中士和士兵原理,展示了自组装系统中高效的性转移.
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