通过非黑米铁 (IV) 氧复合物进行芳香C-F化:结构,光谱和机械研究
Sumit Sahu1, Bo Zhang, Christopher J Pollock
1Department of Chemistry, The Johns Hopkins University , 3400 North Charles Street, Baltimore, Maryland 21218, United States.
Journal of the American Chemical Society
|September 23, 2016
概括
这项研究报告了新的C-F键基化铁复合物. 修改后的配体增强了反应速率,支持了C-F键激活的电友机制.
科学领域:
- 有机金属化学
- 催化剂
- 化学
背景情况:
- 芳香C-F债券很难实现其功能.
- 非海姆铁复合物是氧化反应的多功能催化剂.
- 了解C-F键激活机制对于合成化学至关重要.
研究的目的:
- 合成和表征单核非海姆铁复合物用于分子内芳C-F化.
- 通过研究连接剂替代物的作用来研究C-F键化机制.
- 确定C-F化反应路径和激活障碍.
主要方法:
- 用定制配体 (N4Py2Ar) 合成新的铁复合物.
- 使用单晶X射线衍射,Mössbauer光谱和密度函数理论 (DFT) 的计算进行了表征.
- 使用停止流动的紫外线光谱和艾灵分析的动力学研究.
主要成果:
- 一个关键的FeIV(O) 介质被表现为介质旋转状态.
- 使用-OMe替代剂对C-F化率产生影响.
- 复合3-O显示出显著的速率提升,并确定了激活障碍.
- 证据排除了核友芳香替代途径.
结论:
- 这些数据强烈支持电友C-F化机制.
- 连接物设计对于调整非血铁催化剂的反应性至关重要.
- 这项工作提供了关于惰性C-F债券激活的见解.
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