在Fe-Oxo-Mediated C-H功能化反应中,直接动力学轨迹展示了动态匹配和非统计学基数对中间体
1Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, United States.
Journal of the American Chemical Society
|March 23, 2023
概括
非血氧复合物通过原子转移 (HAT) 与C-H键发生反应. 新的动态揭示了反应选择性是由动态效应驱动的,而不仅仅是中间体,为C-H功能提供了一个新的模型.
科学领域:
- 有机金属化学
- 反应动力学
- 计算化学
背景情况:
- 非血 Fe-oxo 复合体与 C-H 键反应的机制通常涉及原子转移 (HAT) 和激素对中间体.
- 后HAT途径包括激素反弹,解离或脱,影响整体反应选择性.
- 了解这些中间体的动态对于控制C-H功能化至关重要.
研究的目的:
- 研究非血氧复合物与C-H键的原子转移后 (HAT) 反应动态.
- 阐明动态效应和中间结构在确定反应路径选择性的作用.
- 开发一种新的模型来理解非血Fe-oxo介导的C-H功能化.
主要方法:
- 基于密度函数理论 (DFT) 的近古典直动力学轨迹被采用.
- 这项研究重点研究了HAT步骤后的动态.
- 分析轨迹结果以确定反弹,解离和其他途径.
主要成果:
- 根对中间体可能是非统计的,缺乏完整的内部振动再分配.
- 反应选择性主要由动态效应而不是单纯的中间结构来决定.
- 快速反弹通过Fe-OH键旋转和基碰撞之间的动态匹配发生,绕过明显的基对中间体.
结论:
- 动态效应,特别是非同步的协同过程,在C-H功能选择性中发挥着关键作用.
- 激素对中间体是短暂的,它的结构可能不能完全决定反应结果.
- 这项研究为理解非血 Fe-oxo介导的 C-H 功能的选择性提供了新的视角和模型.
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