抄録
Examinations were made on the electrode reaction of the first group of sulfanilamide derivatives and following points were noted as their polarographic behavior:
1) The wave height was higher, the greater the acidity of the aqueous solution of such derivatives. Reduction wave did not appear in the presence of more than equimolar amount of alkali hydroxide and the sodium salt of such derivatives did not show any reduction wave. The wave height is greatly affected by the amount of dissolved oxygen.
2) The first group sulfanilamide derivatives behave more like acetic acid than hydrochloric acid in the effect of kind and content of organic solvent and in relationship between the concentration of sulfanilamide and half-wave potential.
3) Constant-voltage electrolysis results in increase of pH value with decrease of current density, and there is no change in the molecular structure of the sulfanilamide derivatives before and after electrolysis. Reduction wave of the first group sulfanilamide derivatives cannot be considered as the contact wave in which the amino group in para-position takes part.
From such a behavior, it was assumed that the reduction wave of the first group sulfanilamide derivatives was due to the dissociation of hydrogen from a weak acid, as in the case of acetic acid.
