A series of N1-substituted 3,4-dihydropyrimidone -2(1H)-ones were synthesized by an one -pot three-component condensation of aromatic aldehydes ,β-ketone esters and monosubstituted (thio)urea in the presence of FeCl 3 · 6H2 O under solvent -free conditions at 80℃.The effects of the ratio of the raw materials , the amount of the catalyst and thereaction temperature on the yields were investigated .The optimal conditions are as follows:naldehyde:nester:nurea =1:1:1, FeCl3 · 6H2 O is 3 mol％, reaction temperature is 80℃.The reactions of various aromatic aldehydes , ethyl acetoacetate (methyl acetoacetate ) and monosubstituted (thio)urea were investi-gated .Eight new compounds were synthesized .All products were characterized by IR ,1 H NMR, 13 C NMR and ele-mental analysis .The probable catalytic mechanism was proposed .The method has the advantages of simple proce-dure, the avoidance of the use of organic solvents , mild conditions, inexpensive catalyst and extensive substrates .%无溶剂、80℃条件下,三氯化铁为催化剂,芳香醛、β-酮酯、单取代(硫)脲三组分"一锅法"高效合成了一系列N1-取代的3,4-二氢嘧啶酮.考察了原料配比、催化剂用量和反应温度对产率的影响,确定较佳反应条件为:n醛:n酯:n脲=1:1:1,三氯化铁3 mol％,反应温度80℃.在较佳反应条件下,考察了各种芳香醛、乙酰乙酸乙酯(乙酰乙酸甲酯)、单取代脲(硫脲)的反应效果,并合成了八种新物质.所有产品结构通过IR、1 H NMR、13 C NMR和元素分析进行表征.最后提出了可能的催化作用机理.该方法具有操作简单、不使用任何有机溶剂、反应条件温和、催化剂廉价易得、底物范围广等优点.
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