Synthesis and Electrochemical Study of 1-[2′, 4′-dinitrophenyl)-3, 5-dimethyl-4- [4′′-(substituted)sulphonamoylphenyl] Azopyrazoles

Abstract

Electrochemical behavior of 1-(2',4'-dinitrophenyl)-3,5-dimethyl-4-[4"-(substituted) sulphonamoylphenyl] azopyrazole (DDSPA) was studied in Britton-Robinson (BR) buffer range of pH 3.5–12 at dropping mercury electrode (DME) and glassy carbon electrode (GCE). Cathodic differential pulse polarographic peak is obtained at DME in the pH range 3.5–12. Cyclic voltammogram exhibited a well-defined, irreversible cathodic and anodic peak at GCE. At pH 3.5–12, the reduction peak exhibited a tendency to split into two peaks. The first 8e^- peak has been assigned to the reduction of two nitro groups to hydroxylamine group and second 2e^- peak has been assigned to the reduction of azo group to hydrazono group (–NH–NH–). A product of controlled potential electrolysis (CPE) was characterized by elemental and spectral analysis.

Keywords: azopyrazoles, polarography, voltammetry, CPE, electrochemistry