探索基于罗他森的可切换器官催化剂的激活模式
Victor Blanco1, David A Leigh, Urszula Lewandowska
1School of Chemistry, University of Manchester , Oxford Road, Manchester, M13 9PL, United Kingdom.
Journal of the American Chemical Society
|October 7, 2014
概括
一种新型的罗他森分子机器作为可切换的氨基催化剂. 它通过改变其宏循环位置来控制诸如C-C和C-S键形成等反应,从而实现可调节的催化.
科学领域:
- 超分子化学 超分子化学
- 有机化学 有机化学
- 催化剂是一种催化剂.
背景情况:
- 氨基催化对于功能化碳化合物至关重要.
- 通过外部刺激控制催化活动仍然是一个挑战.
- 罗塔克桑具有设计可切换分子系统的潜力.
研究的目的:
- 为了研究基于罗他森的氨基催化剂的催化活性.
- 通过激活最高占用分子轨道 (HOMO) 和最低不占用分子轨道 (LUMO) 来探索催化机制.
- 为了证明可切换控制的催化转换.
主要方法:
- 一种罗塔xane 的合成,其线程上有两个不同的结合点.
- 利用罗他素作为各种有机反应的氨基催化剂.
- 通过改变宏循环的 in situ 位置来调节催化活性.
主要成果:
- 罗塔xane 通过 iminium 和 enamine 的中间体有效催化了 C-C 和 C-S 键的形成.
- 在核友替代,添加和迪尔斯-阿尔德反应中观察到催化活性.
- 在结合位之间切换宏循环的位置允许"开启"和"关闭"对反应速率的控制.
结论:
- 研究中的罗塔xane 作为可控制的氨基催化酶分子机器.
- 这项工作展示了一种用于外部调节催化过程的新策略.
- 这些发现为开发有机合成中先进的可切换催化剂开辟了道路.
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