Potassium carbonate in poly (ethylene glycol-400) has been found to be a highly effective and efficient medium for the straight forward, convenient, one pot and green synthesis of ethyl 2-substituted phenyl-7-oxo-7H-[1,3,4]- thiadiazolo [3,2-a]- pyrimidine-6-corboxylate and -6-corbonitrile through intramolecular cyclo-elimination of Michael adducts formed between the reaction of 2-amino-5 substituted thiadiazoles with diethyl-2- (ethoxymethylene) malonate and ethyl-2- cyano-3-ethoxyacrylate respectively. The structures of all the new compounds have been elucidated using IR, ¹H and ¹³C NMR, mass spectral data and elemental analyses.

中文翻译：

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通过Aza-Michael加成反应和在聚乙二醇（PEG）中进行分子内环消除反应，一锅合成高效，环保的1,3,4-噻二唑并[3,2-a]嘧啶骨架

已发现，聚（乙二醇-400）中的碳酸钾是一种高效，高效的介质，可用于简单，方便，一锅又绿色地合成乙基2-取代的苯基-7-氧代-7 H- [1， 3,4]-噻二唑[3,2-a]-嘧啶-6-羧酸和-6-羟基通过分子内环消除2-氨基-5取代的噻二唑与二乙基-2-（乙氧基亚丙基）丙二酸酯和2-氰基-3-乙氧基丙烯酸乙酯。使用IR，¹ H和¹³ C NMR，质谱数据和元素分析已阐明了所有新化合物的结构。