Issue 6, 2021

Copper-assisted oxidation of catechols into quinone derivatives


Catechols are ubiquitous substances often acting as antioxidants, thus of importance in a variety of biological processes. The Fenton and Haber–Weiss processes are thought to transform these molecules into aggressive reactive oxygen species (ROS), a source of oxidative stress and possibly inducing degenerative diseases. Here, using model conditions (ultrahigh vacuum and single crystals), we unveil another process capable of converting catechols into ROSs, namely an intramolecular redox reaction catalysed by a Cu surface. We focus on a tri-catechol, the hexahydroxytriphenylene molecule, and show that this antioxidant is thereby transformed into a semiquinone, as an intermediate product, and then into an even stronger oxidant, a quinone, as final product. We argue that the transformations occur via two intramolecular redox reactions: since the Cu surface cannot oxidise the molecules, the starting catechol and the semiquinone forms each are, at the same time, self-oxidised and self-reduced. Thanks to these reactions, the quinone and semiquinone are able to interact with the substrate by readily accepting electrons donated by the substrate. Our combined experimental surface science and ab initio analysis highlights the key role played by metal nanoparticles in the development of degenerative diseases.

Graphical abstract: Copper-assisted oxidation of catechols into quinone derivatives

Supplementary files

Article information

Article type
Edge Article
04 Sep 2020
20 Dec 2020
First published
21 Dec 2020
This article is Open Access

All publication charges for this article have been paid for by the Royal Society of Chemistry
Creative Commons BY license

Chem. Sci., 2021,12, 2257-2267

Copper-assisted oxidation of catechols into quinone derivatives

A. C. Gómez-Herrero, C. Sánchez-Sánchez, F. Chérioux, J. I. Martínez, J. Abad, L. Floreano, A. Verdini, A. Cossaro, E. Mazaleyrat, V. Guisset, P. David, S. Lisi, J. A. Martín Gago and J. Coraux, Chem. Sci., 2021, 12, 2257 DOI: 10.1039/D0SC04883F

This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further permissions from the RSC, provided that the correct acknowledgement is given.

Read more about how to correctly acknowledge RSC content.

Social activity