具有高度选择性的不对称的Rh催化基甲基化异环烯的Rh催化基甲基化
Samir H Chikkali1, Rosalba Bellini, Bas de Bruin
1Supramolecular and Homogeneous Catalysis, van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands.
Journal of the American Chemical Society
|March 20, 2012
概括
新的性二联体使具有高度选择性的不对称的挑战性异环烯的水合成型成为可能. 这一突破为有价值的化物实现了优异的产量和酶选择性,促进了催化合成.
科学领域:
- 有机金属化学 有机金属化学
- 不对称的催化剂.
- 一致性催化剂的同质性
背景情况:
- 非对称的基形成 (AHF) 对于合成性化物至关重要.
- 开发对异环烯酸的AHF有效的配体仍然是一个挑战.
- 之前的方法对于特定的异环基质缺乏高的区域和酶选择性.
研究的目的:
- 为了合成新的性二联体 (氨酸-酸米和氨酸-酸).
- 在Rh催化异环烯的不对称基形成中应用这些配体.
- 研究连接体结构对催化性能的影响,包括区域和酶选择性.
主要方法:
- 合成新的二联体:L1,L2 (氨酸-胺) 和L3a-c (氨酸-胺).
- 2,3-二二,2,5-二二,N-乙-3-罗林和N- (((三-丁氧碳基) -3-罗林的Rh催化不对称的水合成型.
- 使用高压NMR和IR光谱学对催化剂静止状态的表征.
主要成果:
- 干L1和L2实现了对2,3-二二酸的基甲基化进行选择性协调和良好的产量.
- 连接物L3c表现出对2,5-dihydrofuran的区域选择性和高反选择性 (高达91% ee) 的完全切换.
- 实现了对二福兰和3-罗林的AHF报告的最高效果,对罗林衍生物具有优异的区域选择性.
结论:
- 新的二联体对异环烯的Rh催化AHF有效.
- 连接物L3c表现出了显著的多功能性,通过基质修饰,使得它能够通过基质修饰获得化的两个化物.
- 这项工作为具有挑战性的 heterocyclic 基质的区域和 enantioselective AHF 设定了一个新的基准.
相关概念视频
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