Reactions of reducing radicals with 2- and 3-nitroanilines in aqueous solutions: a pulse radiolysis study

Abstract

Reactions of 2- and 3-nitro anilines (2- and 3-NA) with e aq − , H-atoms and one-electron reductants have been studied using pulse radiolysis in aqueous solutions. Reactions of e aq − were found to be quite fast with both 2-NA and 3-NA resulting in their corresponding semi-reduced species which are reducing in nature. Reduction potentials for 2-NA/2-Na•′ have been estimated to be approx. −0.56 Vvs. NHE and that for 3-NA/3-NA•− was found to be between −0.185 V and −0.45 Vvs. NHE. Semi-reduced 2-NA has main absorption peak at 300 nm with a shoulder in the 350 nm region and a broad weak band in the 470–500 nm region, whereas semi-reduced 3-NA possesses an absorption peak at 520 nm. Reducing radicals such as (CH3)2 C•OH and CO 2 •− reacted with 2-NA, producing semi-reduced species, whereas reactions of these radicals with 3-NA produced their corresponding radical-adduct species.