Polarographic evidence for the stability of copper(I) ion in some non-complexing nonaqueous solvents

Chemistry of copper in white wine: a review

“…Copper(I) can be stabilised in the presence of non‐aqueous solvents with weaker complexing tendencies towards Cu(II) than Cu(I), that is weak oxygen donors such as propane‐1‐ol, propan‐2‐ol, and also in the presence of nitrogen donors such as pyridine and triethylamine (Gupta , Nelson et al. ). Ethanol and methanol, however, were found to have little effect in stabilising Cu(I) based on the polarographic study of Nelson et al.…”

“…Ethanol and methanol, however, were found to have little effect in stabilising Cu(I) based on the polarographic study of Nelson et al. (). A more focussed approach to identifying Cu(I) in a wine matrix would be beneficial to clarifying the mechanism of ascorbic oxidation.…”

Cleavage of carbon-carbon bonds. Copper(II)-induced oxygenolysis of o-benzoquinones, catechols, and phenols. On the question of nonenzymic oxidation of aromatics and activation of molecular oxygen

“…(3) MeOH the nature of the oxidation products in other solvents remains uncertain.396 Pyridine is atypical as a solvent for copper compounds, because it solvates Cu(I) very effectively, but apparently solvates Cu(II) relatively poorly 45,46 The oxidation of cuprous chloride in methanol containing pyridine396 gives a deep green, insoluble, crystalline pyridine cupric methoxy chloride complex, I. 4CuCl + O2 + 4py ->-(pyCuC10Me)" + 2H20 (4)…”

Improvement of chalcopyrite dissolution in acid media using polar organic solvents

“…In the search for industrially viable alternative oxidants, cupric sulfate has shown reasonable activity in the presence of ligands that are capable of complexing it in its Cu(I) state (Parker et al, 1975). Although the existence of stable uncomplexed cuprous ion in mixed aqueous/organic solvent was reported over fifty years ago (Nelson et al, 1961), the use of the Cu(II)/Cu(I) redox pair has not been exploited in these leaching media. Fig.…”