In this research a highly efficient one-pot preparation of tricarboxamide derivatives via five-component reactions of isocyanides, aldehydes Meldrum's acid and 2equiv. of amines have been developed in the presence of Fe3O4@SiO2-OSO3H nanocomposite. Nano-Fe3O4 encapsulated-silica particles bearing sulfonic acid was readily recovered using an external magnet and could be reused several times without significant loss of reactivity. The catalyst was fully characterized by VSM, FT-IR, SEM, XRD, EDX and TEM analysis.

Highly effective zinc oxide nanoparticles catalyzed solvent-free synthesis of some tetrahydrobenzo[a]xanthen-11-one derivatives via one-pot multi-component reaction of aldehydes, 2-naphthol and dimedone. The present approach creates a variety of biologically active heterocyclic compounds in excellent yields and short reaction times. Four new compounds are reported. The salient features of the ZnO nanoparticles are: easy preparation, cost-effective, high stability, low loading and reusability of the catalyst. The prepared zinc oxide nanoparticles were fully characterized by EDX, XRD, SEM, IR and TEM analysis.

ZnO nanoparticles as a worthwhile and recyclable catalyst have been used for the one-pot synthesis of 1,8-dioxo-decahydroacridines and 1,8-dioxooctahydro-xanthenes via multi-component reactions under solvent-free conditions. The presented method is mild, environmentally friendly, inexpensive and highly effective to give the products in good to excellent yields.

Las nanopartículas de ZnO se han utilizado como catalizador valioso y reciclable para la síntesis de un solo paso de 1,8dioxo decahidroacridinas y 1,8-dioxooctahydro xantenos a través de reacciones multicomponentes bajo condiciones libres de disolvente. El método presentado es suave, respetuoso del medio ambiente, de bajo costo y altamente eficaz para dar los productos en rendimientos de buenos a excelentes.

A novel, efficient and eco-friendly procedure for the synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes and 1,8-dioxo-octahydroxanthenes is described through one-pot condensation of 2-naphthol and dimedone with aryl aldehydes in the presence of nano silica-supported ferric chloride under solvent-free conditions. The present approach offers several advantages such as short reaction times, high yields, easy purification, recovery and reusability of the catalyst.