在温和的条件下,Cu (II) 催化直接和局部选择性基的基化
Robert J Phipps1, Neil P Grimster, Matthew J Gaunt
1Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UK CB2 1EW.
Journal of the American Chemical Society
|June 12, 2008
概括
一种新的铜催化反应使得在C2或C3位置上可选择性对醇的化. 这种C-H键功能化方法具有广泛的范围,并由内控制.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 药用化学 医学化学
背景情况:
- 在药品和天然产品中普遍存在醇衍生物.
- 选择性地址功能化仍然是一个合成挑战.
- C-H激活提供了一条直接的途径来功能化室内支架.
研究的目的:
- 开发一种新的局部选择性方法来进行内结合.
- 为了实现对C2与C3合的控制.
- 探索铜催化C-H功能化的机制.
主要方法:
- 铜 (II) 催化C-H键的功能化.
- 在C2或C3位置上选择性地址的合.
- 涉及拟议的Cu (III) - 烯中间体的机制研究.
主要成果:
- 开发了一种新的Cu (II) 催化工艺,用于醇化.
- 基于N替代实现了基于C2或C3结的高位点选择性.
- 证明了广泛的基质范围和功能组耐受性.
- 提出了一种涉及Cu (III) -aryl物种和C3到C2迁移的机制.
结论:
- 开发的方法为合成C2-和C3-化醇提供了一种多功能途径.
- 在中的N替代是控制化位点选择性的关键.
- 这种C-H功能化方法可以进行进一步的合成阐述.
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