“一锅煮”制备Biginelli和Hantzsch两种产物及其结构分析

苯甲醛、尿素和乙酰乙酸乙酯三组分“一锅煮”可以同时制备Biginelli和Hantzsch两种产物。教学中通过改变催化剂种类、反应物料比、反应溶剂等条件，引导学生探讨反应条件的改变对总产率及两种异构体比例的影响。实验中通过薄层色谱来跟踪反应进程，通过柱色谱分离混合物，最后通过熔点、红外光谱对合成的化合物进行结构表征。本实验集无机化学、有机化学、基础分析化学和仪器分析于一体，具有很强的实用性和可操作性，可作为有机化学实验中的综合性、设计性实验开设。

Preparation of Biginelli and Hantzsch Products in One Pot and Structural Characterization

A new comprehensive and designing organic chemistry experiment is introduced. 3,4-Dihydropyrimidinone (Biginelli product) and 1,4-dihydropyridine (Hantzsch product) are synthesized in one-pot of benzaldehyde, urea and ethyl acetoacetate under catalysts. Students are guided to explore the influence of reaction conditions, such as catalysts, material feeding ratio and solvents, on the total yield and the ratio of two isomers. The reaction is monitored by thin layer chromatographic. Biginelli and Hantzsch products are both simultaneously purified by column chromatography and characterized by melting point and IR spectrum. This experiment integrating inorganic, organic, fundamental analysis and instrument analysis, and has very strong practicability and maneuverability. It can be set up as a comprehensive and designing organic experiment.