Table of contents entryThe kinetics of the reactions between 1,4-benzoquinones and hydrogen peroxide were studied.A systematic study of substituent effects revealed a Hammett-like correlation, where the rate of reaction is mainly determined by electronic effects. 3 AbstractThe kinetics and mechanisms of the redox reactions between hydrogen peroxide and 1,4-benzoquinone, 2-methyl-1,4-benzoquinone, 2,6-dimethyl-1,4-benzoquinone, 2-chloro-1,4-benzoquinone and 2,6-dichloro-1,4-benzoquinone were studied in aqueous media using spectrophotometric monitoring. The formation and decay of a hydroxylated 1,4-benzoquinone was detected. The formation of the intermediate was first order with respect to the parent 1,4-bezoquinone and hydrogen peroxide, whereas inverse first order dependence was revealed with respect to hydrogen ion. The decomposition reaction had two parallel pathways: one was first order with respect to the intermediate, while the other showed second-order dependence.The values of the rate constant measured for the formation step were successfully correlated with both the redox potentials of the substituted quinone/hydroquinone systems and the pK a values of the hydroxylated quinone derivatives. Therefore, electronic effects govern the reactivity of the quinones in this process. NMR and GC-MS measurements were carried out to identify the products in the system. Quantum mechanical calculations were also carried out in these systems.4
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.