The conversion of soluble polyoxometalate into insoluble polyoxometalate is considered to be one of the major challenges in synthetic organic chemistry. Here, polyoxometalate was bonded to the salt part of an organic branch immobilized on the silica-coated Fe₃O₄ nanoparticle and characterized using various techniques. The fabricated complex was used as a heterogeneous catalyst in a novel one-pot reaction for synthesis of benzo[4,5]imidazo[1,2-a]pyrimidin-2-ones using aromatic amines, dimethyl acetylenedicarboxylate (DMAD), derivatives of benzaldehyde and 2-aminobenzimidazole in water/ethanol as a green solvent. 21 derivatives of benzo[4,5]imidazo[1,2-a]pyrimidin-2-one were synthesized by this method and fully characterized. The high stability of the catalyst showed that it can be reused for 6 times without decreasing in activity. The combination of new synthetic method, new ferromagnetic heterogeneous nano-catalyst, green solvent and simple separation method were presented in this work.

中文翻译：

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使用磁性纳米颗粒负载的混合催化剂在绿色溶剂中一锅法合成苯并[4,5]咪唑并[1,2-a]嘧啶-2-酮

将可溶性多金属氧酸盐转化为不溶性多金属氧酸盐被认为是合成有机化学的主要挑战之一。在此，多金属氧酸盐与固定在二氧化硅涂覆的Fe ₃ O ₄纳米颗粒上的有机分支的盐部分键合，并使用各种技术进行表征。所制备的络合物用作新型一锅反应中的非均相催化剂，用于使用芳香胺、乙炔二甲酸二甲酯（DMAD）、苯并[4,5]咪唑并[1,2- a ]嘧啶-2-酮的衍生物、苯甲醛和 2-氨基苯并咪唑在水/乙醇中作为绿色溶剂。利用该方法合成了21种苯并[4,5]咪唑并[1,2- a ]嘧啶-2-酮衍生物，并对其进行了充分表征。催化剂的高稳定性表明其可重复使用6次而不降低活性。该工作提出了新的合成方法、新型铁磁多相纳米催化剂、绿色溶剂和简单的分离方法的结合。