氯化亚锡催化“一锅法”合成N1-取代的3,4-二氢嘧啶-2(1H)-酮

以芳香醛、乙酰乙酸乙酯(甲酯)、单取代脲为原料,氯化亚锡为催化剂,在无溶剂、80℃条件下,通过三组分"一锅法"合成了一系列N1-取代的3,4-二氢嘧啶-2(1H)-酮衍生物。考察了催化剂用量和反应温度对产品收率的影响。通过IR、~1H NMR、~(13)C NMR和元素分析对目标产物结构进行确证,提出了可能的催化作用机理。本文的合成方法具有催化剂活性高、廉价易得和反应时间短、条件温和、产率高、绿色环保等优点。

One-pot Synthesis of N1-Substituted 3,4-Dihydropyrimidin-2(1H)-onesCatalyzed by Stannouschloride Dihydrate

N1-Substituted 3,4-dihydropyrimidin-2(1H)-ones were synthesized by an one-pot three components of aromatic aldehydes, ethyl acetoacetate (methyl acetoacetate) and monosubstituted urea at 80 _oC using SnCl₂.2H₂O as a catalyst under solvent-free conditions. The effects of the amount of the catalyst and the reaction temperature on the products yields were studied. The structures of title products were characterized by IR, ₁H NMR, ₁₃C NMR and elemental analysis. A mechanism to rationalize the reaction was proposed. This synthetic method has the advantages of short reaction time, mild reaction conditions, high yield, high activity catalytic, inexpensive catalyst and green protocol, etc.