(3) L. Mester, J. Am. Chem. SOL., 77, 4301 (1955).(4) G. Henseke and H. Kohler, Ann., 614, 105 (1958).(5) An alternate explanation is that anion formation at C-3 in the phenylosazones is inhibited by formation of delocalized anions by ionization of the NH bonds. Formation of i is requisite to further oxidation of the osazone,