通过Rh催化剂被困在超分子金属位置中的Rh催化剂进行选择性水合成型
Cristina García-Simón1, Rafael Gramage-Doria, Saeed Raoufmoghaddam
1Grup de Química Bioinorgànica i Supramolecular, Institut de Química Computacional i Catàlisi, and Departament de Química, Universitat de Girona. Campus Montilivi , Girona E17071 Catalonia, Spain.
Journal of the American Chemical Society
|January 31, 2015
概括
在超分子中封装的奇拉尔催化剂增强了 styrenes 的 enantioselective 水合成型. 这种间接的性控制,类似于酶,增强了先进的不对称催化剂的立体选择性.
科学领域:
- 超分子化学 超分子化学
- 不对称的催化剂.
- 有机金属化学 有机金属化学
背景情况:
- 在甲基化中实现高的区域和酶选择性仍然是一个挑战.
- 状催化剂通常需要精确控制它们的协调球,以获得最佳性能.
- 超分子化学为催化剂设计和控制提供了新的策略.
研究的目的:
- 开发一种超分子催化剂,用于烯的区域和选择性基形成.
- 为了研究催化剂封装在超分子中的催化剂对催化活性和选择性的影响.
- 通过间接的性控制来探索增强性选择性的机制.
主要方法:
- 宏环双复合物和四碳酸甲的协调驱动的自我组装,形成一个非的超分子子.
- 在自组装的子内封装一个性Rh复合体.
- 使用封装和非封装催化剂的区域和酶选择性水合成型反应.
- 频谱分析 (例如,NMR,UV-Vis) 来研究催化剂特性和协调范围.
主要成果:
- 超分子催化剂实现了烯的区域和选择性基形成.
- 与非封装Rh催化剂相比,封装显著增强了奇拉诱导.
- 光谱数据表明,在封装时Rh催化剂的电子特性或第一个协调球没有变化.
- 增强的抗选择性归因于由子环境诱导的第二个协调球的修改.
结论:
- 在超分子内进行催化剂封装可以有效地增强不对称催化剂中的酶选择性.
- 通过模仿酶机制,间接通过空间控制性,是改善立体选择性的可行策略.
- 可调整尺寸的超分子囊对先进的不对称催化剂的未来发展具有重大前景.
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