通过有针对性的C-H键激活,通过芳香胺的高效和选性循环化
Reema K Thalji1, Jonathan A Ellman, Robert G Bergman
1Center for New Directions in Organic Synthesis, Department of Chemistry, University of California-Berkeley, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|June 10, 2004
概括
这项研究引入了第一个用于芳香C-H键激活的高度酶选择性催化反应. 这一突破使得在较温和的条件下,芳香胺的有效和选择性循环利用成为可能.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 不对称的合成方法
背景情况:
- 芳香C-H键的激活是有机合成中的关键转化.
- 开发用于C-H激活的enantioselective方法仍然是一个重大挑战.
- 以前的分子内化方法需要更高的温度.
研究的目的:
- 报告了第一个涉及芳香C-H键激活的高分离选择性催化反应.
- 开发一种高效的催化系统,用于对甲结合的芳香基胺的酶选择性循环.
- 与现有的Achiral系统相比,为了实现更温和的反应条件.
主要方法:
- 使用了一种催化剂,具体是5mol % [RhCl(coe) ]2.2.
- 采用15mol%的 (S) - 乙醇衍生的胺酸联体,以实现对选择性.
- 研究了芳香基胺与基基组的酶选择性循环化.
主要成果:
- 达到高的反选择性,高达96%的EE.
- 在循环化反应中获得量化产量.
- 与阿基拉系统相比,反应温度显著降低 (降低高达75摄氏度).
结论:
- 开发的催化系统代表了对酶选择性芳香C-H激活的重大进步.
- 反应在温和条件下有效地进行,即使在某些基质的室温下也是如此.
- 这种方法为复杂有机分子的不对称合成提供了一个强大的工具.
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