Collect. Czech. Chem. Commun. 1993, 58, 1978-1988

Polarographic Behaviour of Some Arylazotheophyllines

Mohamed I. Ismail and Madlene L. Iskander

Department of Chemistry, Faculty of Science, Ain Shams University, Cairo, Egypt


The polarographic behaviour of a series of arylazotheophyllines was studied in aqueous alcoholic buffer media and in DMF-0.1 M LiClO4 solution. The redox study gave evidence that the azo group is electroactive in aqueous as well as non-aqueous media. A mechanism interpreting the electrode process is proposed and confirmed through the identification of the controlled potential electrolysis products, the use of a model compound and the application of Hamett's σ-E relationship. The physico-chemical characteristics of these compounds, viz. the diffusion coefficient, dissociation constant, ionization potential and electron affinity, are also included.