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41.
An efficient and simple method for the synthesis of new benzopyranopyrimidines via a pseudo four-component reaction of salicylic aldehydes, malononitrile and various amines in the presence of a catalytic amount of LiClO4 is reported. The advantages of this procedure are mild reaction conditions, high yields of products and operational simplicity. 相似文献
42.
An efficient synthesis of new barbiturate salts consist of 2-aminopyridinium moiety by a?n uncatalyzed three-component condensation reaction of C–H acids, pyrimidine-tetraones, and 2-aminopyridines? in refluxing chloroform is reported. The reaction of pyrimidine-tetraones and 2-aminopyridines with ninhydrin in the formation of new barbiturate salts consist of 2-aminopyridinium moiety is also investigated. 相似文献
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44.
An efficient and one-pot synthesis of 2-(2-oxoindolin-3-ylidene)-1,3-dithiole-4,5-dicarboxylates by a three-component condensation reaction of isatins, carbon disulfide and dialkyl acetylendicarboxylates in the presence of Bu3P is reported. Reaction of carbon disulfide and dialkyl acetylene dicarboxylates with acenaphthylene-1,2-dione, ninhydrine and pyrimidine-tetraone resulted in the formation of 2-(2-oxoacenaphthylen-1(2H)-ylidene)-1,3-dithiole-4,5-dicarboxylates, 2-(1,3-dioxo-1H-inden-2(3H)-ylidene)-1,3-dithiole-4,5-dicarboxylates and 2-(2,4,6-trioxotetrahydropyrimidin-5(6H)-ylidene)-1,3-dithiole-4,5-dicarboxylates, respectively, in the same conditions. 相似文献
45.
New methods for the synthesis of spiro compounds containing dihydrofuran and coumarin moieties from 3-bromo-4-hydroxycoumarins as cyclic α-halo compound based on a pyridinium-ylide-assisted three-component tandem reaction is investigated. To the best of our knowledge, employing cyclic α-halo compounds for the synthesis of dihydrofuran-fused coumarin via a pyridinium ylide has not been reported yet. 相似文献
46.
Roya Akbarzadeh Ghazaleh Imani Shakibaei Ayoob Bazgir 《Monatshefte für Chemie / Chemical Monthly》2010,15(1):1077-1081
Abstract
An efficient and simple synthesis of ferrocenyl 3-aminoimidazo[1,2-a]pyridines by the three-component reaction of ferrocenecarboxaldehyde, isocyanides, and 2-aminopyridines in the presence of a catalytic amount of InCl3 in ethanol at room temperature is reported. 相似文献47.
Magnesium oxide (MgO) effectively catalyzes the three-component reaction of aldehydes, amidine systems, and malononitrile or ethyl cyanoacetate to form 4-amino-5-pyrimidine carbonitrile and pyrimidinone derivatives, respectively. The salient features of this method include high conversions, short reaction times, cleaner reaction profiles, and the use of inexpensive and readily available catalyst. 相似文献
48.
Ahmad Shaabani Ayoob Bazgir Mohammad Bagher Teimouri Hamid Reza Bijanzadeh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):833-839
Protonation of reactive 1:1 intermediates produced in the reaction between triphenylphosphine and dialkyl acetylenedicarboxylate by 3-(1-hydroxyethylidene)-2,4-pentanedione leads to vinyl phosphonium salts, which undergo Michael addition with the conjugate base of CH-acid to produce the title compounds in high yield. 相似文献
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50.
A novel four-component reaction approach to the efficient synthesis of triamide and amidodiester derivatives using amines or alcohols, aldehydes and alkyl or aryl isocyanides in the presence of Meldrum's acid as a CH acid, instead of carboxylic acid of Ugi four-component reaction, was studied. 相似文献