催化剂控制的选择性在Ag催化区分C-H氨基化中的起源
Yue Fu1, Emily E Zerull2, Jennifer M Schomaker2
1Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States.
Journal of the American Chemical Society
|February 8, 2022
概括
这项研究揭示了银催化转移反应如何实现选择性C-H氨基化. 了解像联体效应和前体身份等因素可以精确控制C-N键形成的区域选择性.
科学领域:
- 有机金属化学
- 催化剂
- 计算化学
背景情况:
- 银催化转移 (NT) 反应对于从C-H键合成C-N键至关重要.
- 实现催化剂控制的区域分离功能化需要对选择性决定因素有深入的了解.
研究的目的:
- 通过计算来研究酸盐转移反应.
- 阐明C-H氨化中的区域选择性因素.
- 开发一种合理的催化剂和前体选择方法.
主要方法:
- 对Ag催化NT反应的计算研究.
- 对C-H键解离 (BDE),电荷转移,固态排斥和过渡状态环应变的分析.
- 对过渡状态几何形状的辅助联体和原体影响的研究.
主要成果:
- 确定了一种协调的H原子转移 (HAT) / CN键形成机制.
- 连接体和前体标识显著影响过渡状态对BDE的敏感性,长和电子效应.
- 建立了催化剂和前体选择的预测模型.
结论:
- 这项研究为控制Ag催化NT反应区域选择性的因素提供了统一的理解.
- 针对异位C-H氨基化的合理设计策略已被开发并通过实验验证实.
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