An efficient and metal-free oxidative aromatization of alkyl or aryl-substituted derivatives of 1,4-dihydropyridines and urazoles has been studied using poly-(4-vinylpyridinium nitrate) in the presence of silica sulfuric acid (SiO2-OSO3H). The reaction was carried out in dichloromethane at room temperature and the products were isolated in good to excellent yields.
