Second reduction potentials of some nitroaromatic compounds cycue voltammetric studies

Abstract

Second reduction potentials of some nitroaromatic compounds, 3-Nitroaniline, 4-Nitroaniline. 4-Amino-3-Nitrotoluene, I-Nitronaphthalene and l,3-Dinitrobenzene have been studied by single sweep triangular wave cyclic voltammetry. To check the accuracy and reporducibility of results, investigati~were carried out first using gold wire as reference electrode and then using ig/AgN03 as reference electrode. It was found that the first reduction potentials of the compounds studied were reversible. The second reduction potentials were found to be irreversible for all the compounds except l,3-Dinitrobenzene. To check the reversibility and irreversibility different types of cr iter i a were used. It was found that for the fi rs t reduc t ion potent i a I s Up >c/ Up )a= I, (E"I2)&=( El/i a' Ep - El/~ 28 to 30 mV, Ep/2-EI7228 to 30 mV, and (Ep)c -(Ep ) .. ~ 58 to 60 mV and the value ofiXn ~ 1 all prove that the 1st reduction potentials are reversible. USing the s.me criteria, second reduction potentials were found to be irreversible and the value of om found was approximately 0.3, which also confirms that they are irreversible. Thus the overall picture emerged as multistep reversible-irreversible processes.