Reactions of pyridin-3-ol with pulse-radiolytically generated reducing species

Abstract

Rate constants for reactions of hydrated electron, hydrogen atom, and other reducing radicals such as (CH₃)₂COH and CO₂ ^– with pyridin-3-ol at different values of pH have been determined using the pulse-radiolysis technique. The absorption spectra of the transient product species and kinetic parameters pertaining to them have been investigated. Of the above reducing species all except e^– _aq lead to transient species other than the one-electron reduction product of pyridin-3-ol. (CH₃)₂ĊOH and CO₂ ^– radicals are found to add on to the pyridin-3-ol ring. Pyridin-3-ol radicals formed by reaction with e^– _aq are found to be highly reducing in nature and transfer electrons to thionine, methylene blue, safranine, anthraquinone 2-sulphonate, paraquat, and benzophenone with almost diffusion-controlled rate constants.