催化型选择性C-H化:轴性的有效合成
Qiang Wang1, Zhong-Jian Cai1, Chen-Xu Liu1
1State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Lu , Shanghai 200032 , China.
Journal of the American Chemical Society
|June 12, 2019
概括
这项研究呈现了催化C-H化,产生具有高反选择性的轴性性化合物. 这些产品在不对称合成中作为新型性联体和催化剂的前体.
科学领域:
- 有机化学
- 催化剂
- 不对称的合成
背景情况:
- 轴性双是连接体和催化剂的重要组成部分.
- 开发高效的合成纯异构基的方法仍然是一个挑战.
研究的目的:
- 开发一种 (I) 催化的C-H化.
- 合成具有高产量和选择性的新型轴性性异构.
主要方法:
- 使用由[Rh(C2H4) 2Cl]2衍生的催化剂和TADDOL衍生的单酸.
- 采用2-氨酸,2-异氨酸和类似物作为C-H功能化的指导组.
- 通过C-H激活实现了直接结合.
主要成果:
- 合成了一系列具有优异产率 (高达99%) 和异位选择性 (高达97% ee) 的轴性异位选择性.
- 通过合成性氧化来证明产品的实用性.
- 性N-氧化物有效催化了不对称的合,产生具有高反控制的同醇.
结论:
- 建立了对异构的选择性C-H化的一种多功能方法.
- 合成的性异构是开发新的性配体和催化剂的有价值的前体.
- 该方法使得在不对称的催化过程中可以获得缩化合物.
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