The nitration of phenols in acetic acid

Abstract

It is remarkable to note how little attention has been paid to the study of nitration of aromatic compounds in the advance of organic research. The first papers of interest were those published by Martinsen (J.C.S. 1905, A (ii), 149 and 1907 A (ii), 169). He investigated the nitration of phenol in aqueous solution with increasing acid concentration and recognised the fact that the reaction was auto-catalysed by nitrous acid. Further, he accounted for the effect of substituents in the ring on the rate of nitration. Klemenc (J.C.S. 1919, A. 272) from studies of the nitration of phenol in ethereal solution concluded that the reaction was bimolecular. He found that nitric acid free from nitrous acid or nitrogen peroxide did not cause nitration, and that the rate of the reaction was dependent on the concentration of the nitrous acid. These results agreed with the observations of Brauner on the bromination of benzene in the presence of iodine.