Azo-hydrazo Tautomerism: Further Evidence Based on Polarographic Reduction and Acidity Function of Some Heterocyclic Compounds Containing
نویسنده
چکیده
Potentiometric pKa and polarographic behaviour of I ,3-indandione-monoxime-2-phenyl azo and four of its substituted derivatives were investigated in buffer solution of pH -2-12. The results showed that the compounds are in the azo-form, where its reduction wave precedes that of the oxime. A mechanism for the electrodic processes was proposed. Half-wave potentials showed fair correlation with Hammett's s constants while pKa is practically independent.
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