Reaction mechanism studies on isoquinoline with hydroxyl radical in aqueous solutions

Abstract

The reaction mechanism between isoquinoline and ·OH radical in aqueous dilute solutions under different conditions was studied by pulse radiolysis. The main characteristic peaks in these transient absorption spectra were attributed and the growth-decay trends of several transient species were investigated. Under neutral or alkaline conditions, the reaction of ·OH radical and isoquinoline produces OH-adducts with respective rate constants of 3.4×10⁹ and 6.6×10⁹ mol^-1 · dm³ · s^-1 while under acidic conditions, the isoquinoline was firstly protonated and then ·OH added to the benzene ring and produced protonated isoquinoline OH-adducts with a rate constant of 3.9×10⁹ mol^-1 · dm³ · s^-1. With a better understanding on radiolysis of isoquinoline, this study is of help for its degradation and for environmental protection.

Keywords

isoquinoline, pulse radiolysis, transient absorption spectra, hydroxyl radical