An easy methodology has been developed for the N-arylation of imidazole with arylboronic acid in absence of base and ligand with the aid of as-synthesized CuO nanoparticles. The CuO nanoparticles have been synthesized via precipitation route. The as-synthesized copper oxide nanoparticles are well characterized by various analytical and spectroscopic techniques, such as powder XRD, Raman spectroscopy, TEM and BET surface area analyses. The CuO nanoparticles appear as spherical in shape with a surface area of 15.4 m(2)/g. The mentioned reaction successfully proceeds at moderate temperature in presence of the as-synthesized nanoparticles. The protocol is applicable to a wide variety of electronically diverse precursor moieties signifying its well applicability. Graphical Abstract [GRAPHICS] .