Polarography of Pyridine N-Oxide and its Alkyl Derivatives

The polarographic behavior of pyridine, 4-methylpyridine and 4-ethylpyridine N-oxides has been investigated. The reduction wave of these N-oxides decreases rapidly with the increasing pH value in pH values above 5 and disappears in alkali. It was clearly shown by the polarographic and spectroscopic investigations that the main reason for this phenomenon is the kinetic current. Quantitative treatment of the pH-dependence of the limiting current was also carried out.