超分子催化剂内的旋:离开组控制的产品选择性和机制研究
Qi Zhang1, Lorenzo Catti1, Jürgen Pleiss2
1Department of Chemistry, University of Basel , St. Johanns-Ring 19, CH-4056 Basel, Switzerland.
Journal of the American Chemical Society
|June 8, 2017
概括
研究人员开发了一种人造的类似酶的催化剂, 这种使用非共价相互作用的氨酸囊使得可调节的产品具有选择性,并且需要酸痕迹来产生协同催化作用.
科学领域:
- 超分子化学
- 有机催化剂
- 酶模拟技术
背景情况:
- 尾到头的烯循环是一个复杂的自然反应.
- 在复杂的有机转化过程中寻找类似酶的催化剂.
- 素囊提供了一个超分子催化平台.
研究的目的:
- 开发人类制造的第一个类似酶的催化剂,
- 研究催化反应的机械细节和选择性控制.
- 了解非共价相互作用和催化剂在催化过程中的作用.
主要方法:
- 一个基于键的复星囊的设计和合成.
- 从尾部到头部的烯循环的催化,特别是烯酸循环.
- 使用动力学研究和对照实验进行机制研究.
- 通过不同的离开组调整产品的选择性.
主要成果:
- 该囊成功催化了尾部到头部的旋.
- 通过改变基板上的离开组来调整产品的选择性.
- 离开组的分离被确定为决定速度的步骤.
- 微量酸被发现是必要的共催化剂.
- 囊和酸痕迹之间的协同作用对催化非常重要.
结论:
- 这种复杂的烯循环是第一种类似酶的人工催化剂.
- 催化剂可以通过非共价相互作用实现可调的产品选择性.
- 酸性催化是必不可少的,突出显示了超分子宿主和酸性痕迹之间的协同机制.
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