An environmental friendly, economical and clean Biginelli approach in presence of readily available zinc acetate dihydrate (Zn(OAc)₂.2H₂O) to access biologically active 3,4-dihydropyrimidin-2-(1H)-ones/thiones derivatives via one-pot, three-component reaction of β-keto esters (methyl or ethyl acetoacetate), aromatic aldehyde (benzaldehye derivatives) and urea or thiourea in high to excellent yields has been studied. This solvent-free procedure is sustainable and advantageous compared to conventional methods due to short reaction times, one-pot procedure, easy handling, efficient, environmentally benign nature, low-cost and non-toxic catalyst, eco-friendly, ready availability of starting materials and no requirement of chromatographic purification. The products have been characterized by melting points and ¹H NMR spectroscopy.

中文翻译：

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使用Zn（OAc）2.2H2O作为环境友好，易用和高效的催化剂，清洁和一锅合成3,4-二氢嘧啶-2-（1H）-一/硫酮衍生物的生态安全无溶剂方法

在容易获得的存在下，在环境友好的，经济的和干净的Biginelli方法锌二水合乙锌（Zn（OAc）₂ ·2H ₂ O），以获得生物活性的3,4-二氢-2-（1- ħ） -酮/硫酮衍生物通过研究了β-酮酯（乙酰乙酸甲酯或乙酸乙酯），芳族醛（苯扎德基衍生物）与尿素或硫脲的一锅三组分反应，产率高至优异。与常规方法相比，该无溶剂方法具有可持续性和优势，因为它具有反应时间短，一锅操作，易于操作，高效，环境友好的特性，低成本且无毒的催化剂，生态友好，易于使用的起始方法材料，无需色谱纯化。产品已通过熔点和¹ H NMR光谱进行了表征。