Insights into the Chemistry and Structural Features of the Copper(ii) 2,2′-Bipyridyl–Thiosulfate System

In this paper, we present our findings on a series of copper(ii) 2,2′-bipyridyl (bipy) complexes that inhibit the oxidation of thiosulfate, a current problem in the gold leaching process. The formation of six complexes, five of which have been structurally characterized by X-ray crystallography, illustrate a thermally induced, controllable switching between oxidation states, which in turn inhibits the oxidation of thiosulfate. These findings give further insight and understanding into the rich chemistry of the coinage metals and the hydrolytic processes involved with gold leaching.