Catechol/o-benzoquinone exchange at gold(iii)

Abstract

Although gold(III) chemistry has tremendously progressed in the past 2 decades, gold(III) catecholate complexes remain extremely scarce and underdeveloped. Upon preparation and full characterization of P^C-cyclometalated gold(III) complexes, we serendipitously uncovered an intriguing catechol exchange process at gold(III). Electron-rich catecholates turned out to be readily displaced by electron-poor o-benzoquinones. DFT calculations revealed an original path for this transformation involving two consecutive Single Electron Transfer events between the catecholate and o-benzoquinone moieties while gold maintains its +III oxidation state. This catechol/o-benzoquinone exchange at gold(III) represents a new path for the exchange of X-type ligands at transition metals.