可光切换的催化剂:通过结合实验和计算方法将结构和形状动力学与反应性相关联
Ragnar S Stoll1, Maike V Peters, Andreas Kuhn
1Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany.
Journal of the American Chemical Society
|December 9, 2008
概括
研究人员开发了可光切换的催化剂,通过光来改变它们的基本性和反应性. 这允许通过开启或关闭催化剂来精确控制化学反应,如醇反应.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 摄影化学的使用.
背景情况:
- 皮佩里丁衍生物的布伦斯特基性对于基性催化是至关重要的.
- 通过光等外部刺激控制催化剂活动是合成化学的一个关键目标.
研究的目的:
- 开发具有可调节的布伦斯特德基本性的可光切换催化剂.
- 为了证明在一般基础催化中催化剂活性的光控制,特别是罗阿尔多尔反应.
主要方法:
- 合成来自亚博和斯蒂尔的可光交换基.
- 用X射线晶体学来确定催化剂异构体的固态结构.
- 使用残极二极合 (RDC) 的NMR光谱学来研究构造动态.
- 密度函数理论 (DFT) 计算用于结构分析和质子亲和力.
主要成果:
- 加入一个重的亚博烯组调制的皮佩里丁基性.
- 在E (OFF) 和Z (ON) 同位体之间观察到显著的反应性差异.
- 催化剂活性的光调节在尼特罗阿尔多尔反应中被成功证明.
- X射线结构揭示了E异构体中受阻的活性部位和Z异构体中可访问的部位.
结论:
- 可光切换的piperidine衍生物使光控制的一般基质催化成为可能.
- 开发的模块化合成路线可以访问各种可光开关的催化剂.
- 结构和动态研究将催化剂构成与反应性相关联,使合理设计成为可能.
相关概念视频
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