通过C-H激活进行的Achiral Cp*Rh(III) /Chiral Lewis基合作催化
Takumaru Kurihara1, Masahiro Kojima1, Tatsuhiko Yoshino1,2
1Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan.
Journal of the American Chemical Society
|April 11, 2022
概括
一个新的合作催化系统使得合成zolactams的C-H激活成为可能. 这种方法利用复合物和化易斯基,实现高产量和优异的反选择性.
科学领域:
- 有机化学
- 催化剂
- 合成方法
背景情况:
- C-H激活是有机合成的一个关键策略.
- 开发用于C-H功能化的酶选择性方法仍然是一个重大挑战.
- 合作催化提供了一种增强反应性和选择性的有希望的方法.
研究的目的:
- 通过C(sp2) -H激活开发一个enantioselective [4+3]循环.
- 建立一个使用Cp*Rh(III) 复合体和易斯基的合作催化系统.
- 合成具有高反选择性的多种zolactams.
主要方法:
- 采用一个合作催化系统,包括一个Cp*Rh (III) 复合物和一个合性异基氨酸催化剂.
- 产生一个α,β不和的酸中间体.
- 将中间体与由催化剂和胺衍生物形成的金属循环反应.
主要成果:
- 通过C(sp2) -H激活成功进行反选择性 [4+3]循环.
- 在良好的产量中合成各种zolactams.
- 获得了高达99:1的优异异选择性.
结论:
- 合作催化系统有效控制过渡金属催化C-H功能化中的反选择性.
- 易斯基催化是一种强大的非对称合成工具.
- 这种方法可以有效地获取基丰富的zolactams.
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