由MnO4 - - 激活基的BF3氧化
William W Y Lam1, Shek-Man Yiu, Joyce M N Lee
1Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong, China.
Journal of the American Chemical Society
|March 2, 2006
概括
三化物 (BF) 在室温下显著加快甲 (KMnO) 的C-H键的氧化. 活性物种是BF(3) -KMnO(4) 添加物,可快速氧化和.
科学领域:
- 有机化学 有机化学
- 反应动力学反应动力学
- 计算化学的计算化学
背景情况:
- 甲 (KMnO(4)) 是一种常见的氧化剂,但其与C-H键的反应性,特别是中,通常是有限的.
- 易斯酸可能会调节 permanganate 氧化反应的反应性.
研究的目的:
- 调查三化物 (BF) 对KMnO (KMnO4) 氧化和基的催化作用.
- 为了阐明对加速氧化负责的活性物种和反应机制.
主要方法:
- 实验研究涉及光谱光度和动力学,以表征BF(3) -KMnO(4) 引述和测量反应速率.
- 确定各种碳化合物基质的动态同位素效应.
- 密度函数理论 (DFT) 计算以建模反应机制和能量障碍.
主要成果:
- BF(3) 极大地加速KMnO(4) C-H键的氧化,使室温反应成为可能.
- 活性物种被确定为[BF{3}.MnO{4}{4}}-) 添加物,其反应性比单独的MnO{4}{4}{4}}{4}{4}}{4}{4}{4}}{4}{4}{4}}{4}{4}{4}{4}{4}{5}{6}{7}{8}{8}{9}}{9}{9}{9}{9}}{9}{9}}{9}{9}{9}{9}{9}{9}{9}{9}{9}{9}{9}{9}{9}}{9}}{9}{9}{9}}{9}}{9}}{9}}{9}}{9}{9}}{9}}{9}}{9}}{9}{9}}{9}}{9}{9}{9}{9}}}{9}{9}}}
- 动态同位素效应和与C-H键能量的相关性表明原子转移是限制速度的步骤.
- DFT计算证实了BF(3) 协调降低了反应障碍,稳定了过渡状态.
结论:
- BF(3) 作为KMnO(4) 氧化的一种强有力的催化剂,显著提高其对C-H键激活的效率.
- [BF{3).MnO{4) ]{-) 添加物是关键的反应中间体,通过原子转移促进快速氧化.
- 计算和实验数据提供了对这种加速氧化过程的全面了解.
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