使用大量的氨基基激素和区域选择性的DFT分析进行指导无组C (sp2H) -H氨基化
Nicole Erin Behnke1, Young-Do Kwon1, Michael T Davenport2
1Department of Chemistry, Rice University, Houston, Texas 77030, United States.
The Journal of organic chemistry
|July 28, 2023
概括
研究人员开发了一种新的C-H氨化方法,使用铁催化剂和氧胺试剂. 这一过程产生了一种庞大的氨基基中间体,使功能化中的可预测的区域选择性成为可能.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 计算化学的计算化学
背景情况:
- 电友氨基试剂对于将的功能组引入有机分子至关重要.
- 在C-H功能化反应中控制区域选择性,特别是氨化,仍然是合成化学的一个重大挑战.
- 铁催化为各种有机转化提供了一种可持续且具有成本效益的方法.
研究的目的:
- 通过TMSOTf或TFA激活的新型氧胺衍生物试剂和铁 (II) 催化剂来研究C-H氨化机制.
- 在一系列被替代的基上探索这种氨化反应的区域选择性.
- 基于计算分析,为主要的amination产品开发一个预测模型.
主要方法:
- 从基胺前体中生成一种短暂的氨基基中间体.
- 使用易斯酸 (TMSOTf或TFA) 的激活和从铁 (II) 催化剂的电子转移.
- 密度函数理论 (DFT) 计算用于研究反应途径和区域选择性.
主要成果:
- 反应通过一种短暂且庞大的氨基基中间体进行.
- DFT的计算成功地模拟了C-H氨基化在替代的区域选择性.
- 建议并验证了一种负载控制的区域选择性模型.
结论:
- 开发的方法为的电友氨化提供了一条新的途径.
- 拟议的电荷控制模型有效地预测了arene C-H amination 的区域选择性.
- 这项工作促进了对铁催化C-H功能化反应的理解和应用.
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