由胺激发的基的形式基C (sp3) -H键激活
Wei Bao1, Hanno Kossen1, Uwe Schneider1
1EaStCHEM School of Chemistry, The University of Edinburgh , The King's Buildings, David Brewster Road, Edinburgh EH9 3FJ, U.K.
Journal of the American Chemical Society
|March 16, 2017
概括
胺在中有效催化性C ((sp3) -H键的激活. 这种无过渡金属的方法可以通过C-C键与胺基形成高产合成复杂的胺基.
科学领域:
- 有机化学
- 催化剂
- 合成方法
背景情况:
- 对有机合成至关重要的是基C(sp3) -H键的激活.
- 开发无金属的过渡催化系统仍然是一个重大挑战.
- 选择性C-C键的形成是构建复杂分子结构的关键.
研究的目的:
- 探讨胺对基C ((sp3) -H键的催化潜力.
- 开发一种新的,不使用过渡金属的C-C键形成方法.
- 合成具有高选择性和产量的复杂氨基.
主要方法:
- 使用胺作为基的正式基C ((sp3) -H键激活的催化剂.
- 研究了与各种 imines 的后续 C-C 键形成反应.
- 使用了温和的反应条件,并分析了产品的选择性.
- 使用核磁共振 (NMR) 和高分辨率质谱 (HRMS) 进行反应中间体的特征.
主要成果:
- 在温和的条件下实现有效的基C ((sp3) -H键激活.
- 在C-C键构成中表现出高产量,完全的区域选择性和出色的几何选择性.
- 对芳香,和的功能表现出耐受性.
- 在单个步骤中成功合成了具有CC双键和异芳性单元的复杂氨基.
- 确定了两种具有催化作用的基中间体.
结论:
- 胺是一种高效的催化剂,可激活基C-sp3H和随后的C-C合.
- 这种无金属过渡方法为复杂的氨基提供了可持续和有效的途径.
- 这项研究强调了在催化中的独特作用,并提供了对反应机制的洞察力.
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