高度Z-选择性和enantioselective环开放/交叉转移被一个已解决的立体-at-Ru复合物催化
John Hartung1, Robert H Grubbs
1Arnold and Mabel Beckman Laboratories of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States.
Journal of the American Chemical Society
|July 5, 2013
概括
研究人员开发了一种新型的催化剂,用于Z选择性非对称环开放/交叉转移反应. 这种催化剂实现了高的Z选择性 (高达98%) 和反选择性 (高达95%).
科学领域:
- 有机金属化学 有机金属化学
- 不对称的催化剂.
- 有机合成 有机合成
背景情况:
- 不对称的环开放/交叉转移是有机合成中的一个关键转变.
- 开发具有高度选择性和enantioselective催化剂仍然是一个重大挑战.
- 基于的催化剂已被广泛探索为olefin转化反应.
研究的目的:
- 合成一种新型的复合物,用于不对称的环开放/交叉转移.
- 在催化过程中实现高Z选择性和选择性.
- 通过奇拉分辨率展示一种用于催化剂制备的新方法.
主要方法:
- 一个含有化N-异环碳联体的鲁丁复合物的合成.
- 使用奇拉性碳酸盐的N-异环碳酸复合物的分离.
- 在不对称的环开放/交叉转移反应中,合成的鲁丁复合物的应用.
主要成果:
- 合成的鲁复合物有效地催化了Z-选择性的不对称环开放/交叉转移.
- 在反应中达到高达98%的Z-选择性.
- 证明了高的反反选择性,达到高达95%的反反体过量 (ee).
结论:
- 成功合成了一种新型的催化剂,可实现高度Z选择性和酶选择性非对称环开放/交叉转移.
- 用性碳酸盐替代联体是一种有效的策略,用于解决化N-异环碳酸盐复合物的化.
- 这种催化剂代表了对不对称的烯转化物的重大进步.
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