Dinitrogen tetroxide complexes of iron and copper nitrates as new reagents for selective mono- and dinitration of phenolic compounds

Fe(NO3)(3-)1.5 N2O4 and Cu(NO3)(2-) N2O4 are easily prepared reagents for the efficient and selective mono-or dinitration of phenolic compounds. In comparison with metal nitrates, these complexes resemble a synergetic effect on the rates and the yields of the reactions. High ratio of p-nitrophenol formation vs o-nitrophenol is also observed in the mononitration reactions.