三乙胺对酰氯/烯醇酯化反应的影响——介绍一个探索性有机化学实验

The effect of triethylamine during the esterification reaction of acyl chloride with enol

乙酰氯与3-甲基-3-丁烯-1-醇直接反应得到乙酸(3-甲基-3-氯)丁酯,而在向反应体系中添加三乙胺后则得到乙酸(3-甲基-3-丁烯)酯,产物结构通过核磁共振氢谱(1H-NMR)和傅立叶红外(FTIR)光谱分析确证。乙酸(3-甲基-3-丁烯)酯的生成机理包含亲核加成-消除和亲电加成两步。而在三乙胺的存在下,只有亲核加成-消除一步而得到乙酸(3-甲基-3-丁烯)酯。本实验由相同的原料在相同操作下,通过简单的反应条件调控得到不同的产物。通过本实验的开设,有助于培养学生的创新能力。

3-chloro-3-methyl-1-butyl acetate was obtained by the reaction of acyl chloride with 3-methyl-3-beten-1-ol, while 3-methyl-3-betene acetate was obtained when triethylamine was added. The structure of the products was confirmed by 1 HNMR and FT-IR spectroscopy. The mechanism of the preparation of 3-chloro-3-methyl-1-butyl acetate includes two steps: nucleophilic addition elimination and electrophilic addition. While nucleophilic addition elimination was proceed with the addition of triethylamine. Different products were obtained from the same raw materials under the same operation by simple reaction conditions. Students' innovative ability was cultivated through this experiment.