Synthesis, characterisation and catalytic studies of nano zinc oxide-alumina for displacement reaction on carbonyldiimidazole

Nano zinc oxide supported on alumina was prepared by chemical method and calcined at 300o C. The calcined material was characterized by UV-Visible spectroscopy, Infra-Red spectroscopy, X-Ray Diffraction technique, Scanning Electron Microscopy, Thermogravimetric analysis and Porosimetry. The catalytic activity studies on alumina supported zinc oxide for the synthesis of disubstituted ureas through displacement reaction on carbonyldiimidazole are hitherto unreported. Thus, alumina supported nano zinc oxide was tested for its catalytic activity in the displacement reaction of carbonyldiimidazole with cyclohexylamine. While, the above reaction when carried out at room temperature, afforded 1,3-Dicyclohexyl urea, as the sole product in 88% yield in 20 hours, at 80o C, 1,3-dicyclohexyl urea was obtained in 80% yield, in 4 hours. Reusable and safer catalysts, reaction at room temperature, simple workup and product with good yield and purity are the merits of this process.