Present work involves the synthesis of substituted dimethyl octahydroquinazolinones by using electrochemically prepared copper oxide nanoparticles as catalyst in microwave. Copper oxide nanoparticles were prepared in appreciable yield by using electrochemical reduction method of synthesis in the presence of tetrabutylphosphonium bromide for capping. The prepared nanoparticles were analyzed by UV, FTIR, TGA, X-ray diffraction and electron microscopic studies. The nanoparticles of copper oxide then were successfully used as a catalyst in multicomponent reaction between diketones, substituted aldehydes and urea/thiourea to synthesize substituted dimethyl octahydroquinazolinones.
Using an efficient and eco-friendly approach, 14 4-aryl-7,7-dimethyl-1,2,3,4,5,6,7,8-octahydroquinazolin-2,5-diones (and six of their 2-thione analogues) were prepared in good yields and in short reaction times by a three-component reaction of an araldehyde, dimedone and urea (or thiourea) using Fe3O4 nanoparticles in aqueous ethanol under reflux conditions. The Fe3O4 nanoparticles, which were easily prepared and could be recycled, were fully characterised by TEM, SEM, XRD, EDX, VSM and FTIR analysis.