梁高珲

The coronavirus is spread through the air, especially in indoor spaces. While it is not as infectious as measles, scientists now openly acknowledge the role played by the transmission of aerosols – tiny contagious particles exhaled by an infected person that remain suspended in the air of an indoor environment. How does the transmission work? And, more importantly, how can we stop it?

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概要

β-酮酯与醛，含氮化合物的多组分反应，反应生成二氢吡啶化合物。二氢吡啶继续被氧化可以转化成吡啶产物。

基本文献

• Hantzsch, A. Ber. 1881, 14, 1637. doi:10.1002/cber.18810140214
  
• Hantzsch, A. Ann. 1882, 215, 1, 72.
• Singer, A.; McElvain, S. M. Org. Synth. 1934, 14, 30. [website]
• Kellog, R. M. et al. J. Org. Chem. 1980, 45, 2854. DOI: 10.1021/jo01302a020

反应机理

首先通过Knoevenagel缩合生成缺电子的烯烃，然后与氨反应生成烯胺，然后进行Micheal加成，脱水缩合得到产物。

反応例

Nifedipine的一步合成法

实验步骤

实验技巧

参考文献

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