perfluorinated aryl azides 的1,3-双极循环添加反应性与胺和压力双极的双极
Sheng Xie1, Steven A Lopez, Olof Ramström
1Department of Chemistry, KTH-Royal Institute of Technology , Teknikringen 36, Stockholm, Sweden.
Journal of the American Chemical Society
|January 2, 2015
概括
perfluoroaryl azides (PFAAs) 在与酶胺的循环添加中反应的速度明显快于酸. 这种增强的反应性源于PFAA.
科学领域:
- 有机化学 有机化学
- 化学动力学 化学动力学
- 计算化学计算化学
背景情况:
- perfluoroaryl亚化物 (PFAA) 是一种高度反应性的电友亚化物.
- 胺是富含电子的核性基.
- 了解这些类化合物的反应性对于合成应用至关重要.
研究的目的:
- 为了研究胺和压力双极的反应性与 perfluoroaryl 亚化物 (PFAAs).
- 阐明导致观察到反应速度加速的因素.
- 为了比较循环添加产品及其稳定性与使用酸形成的产品.
主要方法:
- 实验动力学研究以确定反应速率.
- 密度函数理论 (DFT) 计算以探索反应机制和轨道相互作用.
- 反应产品的特性. 反应产品的特性.
主要成果:
- 酸经历 (3+2) 循环添加与酶胺,速度高达比酸快4个数量级.
- DFT计算显示,由于PFAA的低LUMO,更大的轨道相互作用是速度加速的原因.
- 从PFAA-胺循环添加物中形成的特里亚佐林重新排列为阿米丁,与来自酸反应的稳定特里亚佐林不同.
- 与酸相比,像norbornene和DIBAC这样的紧张双极分子也表现出与PFAA的增强反应性,尽管比酶胺更慢.
结论:
- 与酸相比, perfluoroaryl 化物在 (3+2) 循环添加与酶胺的反应性显著增强.
- 酸的电子特性,特别是它们的低LUMO,是这种加速反应的关键驱动因素.
- 由PFAA-胺反应产生的三氨酸的不稳定性导致进一步的重组,与烯酸反应相比,提供不同的合成途径.
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