A grit like nanostructure of MgO was prepared in a medium of mulberry leaves extract and characterized on the basis of field emission scanning electronic microscopy (FE-SEM), X-ray diffraction (XRD), and energy dispersive X-ray (EDX) analysis. It was found to be an efficient catalyst for one-pot synthesis of 4H-pyrans from the reaction of malononitrile and α,α′-bis(substituted-benzylidene) cycloalkanones in good to high yields.
