一个研究型含氟杂环化合物实验的设计

An Exploration-oriented Experimental Design on Chemoselective Synthesis of Fluorinated Heterocycles

设计了一个由底物控制的化学选择性合成含氟吡唑、哒嗪酮和吲哚衍生物的实验。此研究型实验是以不同碳链长度的β,γ和δ-含氟酮酸酯为底物与苯肼在对甲苯磺酸的作用下,以甲苯为溶剂一锅反应分别得到具有潜在生理活性的含氟吡唑、哒嗪酮和吲哚衍生物。实验操作简便、反应条件温和。反应的进程可用TLC和19F NMR谱跟踪。产物结构经红外光谱、核磁共振氢谱、氟谱和碳谱及元素分析等表征和确定,对底物控制的化学选择性形成不同的产物进行了分析,并对此研究型实验在实验教学工作中的实践效果进行了探讨。

A simple and facile exploring organic chemistry experiment was designed on a substrate-controlled chemoselective one-pot synthesis of biologically interested trifluoromethylated heterocycles,such as indoles,dihydropyridazinones and pyrazole-3-ol derivatives,through the different chain length of substrates of（-trifluoromethyl substituted（,（,（-ketoesters reacting with phenylhydrazine under the promotion of p-TsOH in the toluene.The experimental results were traced by TLC or 19F NMR,and the structure of the products were analyzed and confirmed by IR,1H NMR,13C NMR,19F NMR and elemental analysis.Plausible reaction pathway from ketoesters to indole or 1,2-diaza-3-one heterocycles was deduceed.Practical effects in the experimental teaching were discussed as well.