three-component synthesis of 2-amino-4-substituted-1,4-dihydrobenzo[4,5]imidazolo[1,2-a]pyrimidine-3-carbonitrile derivatives by the reaction between various aldehydes with 2-aminobenzimidazole and malononitrile with an excellent output and in low-response period was studied in the presence of Ag–TiO2 nanocomposite as an efficient and recyclable catalyst undersolvent-freeconditions at 60 °C. The results
摘要通过各种醛与2-的反应,一锅三组分合成2-氨基-4-取代的1,4-二氢苯并[4,5]咪唑并[1,2 - a ]嘧啶-3-腈在无溶剂条件下于60°C的条件下,以Ag-TiO 2纳米复合材料作为有效和可回收的催化剂,研究了氨基苯并咪唑和丙二腈具有优异的产量和低响应时间。结果表明,所需产物的分离可通过简单过滤实现,并且Ag-TiO 2纳米复合材料可重复使用并连续重复使用。 图形摘要
Poly(vinylpyrrolidonium) perchlorate catalyzed one-pot synthesis of tricyclic dihydropyrimidine derivatives
A simple and efficient procedure for the synthesis of benzo[4,5]imidazo[1,2-α]pyrimidine and 2-amino-4-substituted-1,4-dihydrobenzo[4,5]imidazolo[1,2-α]pyrimidine-3-carbonitrile derivatives using poly(vinylpyrrolidonium) perchlorate [PVPH]ClO4} as a newly reported, modified polymeric catalyst is reported. Some of the advantages of this novel synthetic method are: easy preparation of the catalyst,
p-Toluenesulfonic acid-catalyzed one-pot synthesis of 2-amino-4-substituted-1,4-dihydrobenzo[4,5]imidazolo[1,2-a]pyrimidine-3-carbonitriles under neat conditions
Résumé A simple, efficient, and green procedure for the preparation of 2-amino-4-substituted-1,4-dihydrobenzolo[4,5]imidazolo[1,2-a]pyrimidine-3-carbonitriles has been developed by multi-component condensation of 2-aminobenzimidazole with aldehydes and malononitrile in the presence of a catalytic amount of p-toluenesulfonic acid, affording excellent yields under neat conditions. The protocol avoids the use of expensive catalysts, toxic solvents, and chromatographic separation. We believe that this new environmentally metal-free procedure, combined to a solvent-free reaction, would be of importance in the search of green laboratory-scale synthesis.
ABSTRACT Synthesis of pyrimido[1,2-a]benzimidazole and pyrano[2,3-c]pyrazole derivatives were achieved using polyethylene glycol (PEG-400) as promoting reaction medium in water under catalyst-free conditions at reflux and room temperature, respectively. The structure of pyrimido[1,2-a]benzimidazole was confirmed using 1H NMR, 13C NMR, DEPT, and HMBC experiments. The promising points for the present
Starch functionalized magnetite nanoparticles: A green, biocatalyst for one-pot multicomponent synthesis of imidazopyrimidine derivatives in aqueous medium under ultrasound irradiation
efficient and environmentally friendly one-pot multicomponent synthesis of biologically fascinating imidazopyrimidine derivatives by the reaction of aromatic aldehydes, active methylene compounds and 2-aminobenzimidazole under ultrasonic irradiation have been developed. The reaction is catalyzed by starch functionalized magnetite nanoparticles (s-Fe3O4). The salient features of the present methodology