罗 (III) 催化不对称的含有1,6-二烯的玻利循环:一个实验和DFT研究
Yun-Xuan Tan1, Fang Zhang2, Pei-Pei Xie3
1CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Center for Excellence in Molecular Synthesis , Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China.
Journal of the American Chemical Society
|July 27, 2019
概括
这项研究引入了第一个 (III) 催化不对称的1,6dienes的化循环. 该方法有效地产生具有多个立体中心的光学纯粹的 cis-双环化合物.
科学领域:
- 有机化学
- 催化剂
- 立体选择合成
背景情况:
- 在金属催化不对称的1,6-二烯循环中区分烯本身很困难.
- 在有机化学中,开发用于合成多个立体中心的复杂双循环结构的高效方法仍然是一个挑战.
研究的目的:
- 开发第一个 (III) 催化不对称的化循环,
- 在光学纯净的cis-bicyclic骨架合成中实现高产量和立体选择性.
主要方法:
- (III) 催化不对称的化循环反应.
- 使用循环二连接的单基,1,1-二基和 (E) -1,2-二基 (1,6-二基) 替代物.
- 使用SAESI-MS (扫描电喷射离子质谱) 和计算研究来阐明催化循环.
主要成果:
- 成功合成了光学纯净的三或四个连续的立体中心的 cis-cyclic 骨架.
- 获得高产量 (25-93%) 和优异的二元选择性 (> 20:1 dr) 和异位选择性 (90- 99% ee).
- 已证明与广泛的功能组兼容,可轻松进行产品转换.
结论:
- 确立了一种新型的 (III) 催化不对称的1,6-dienes的化循环.
- 提出了Rh (I) / (III) 催化循环,其中包括氧化添加,油脂插入,合添加和还原性消除等关键步骤.
- 突出了环应变在控制区域选择性和促进5,6双循环结构的作用,为未来的反应设计提供了基础.
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