Copper complexes sulfur ligands

It has been recognized that sulfur donors aid the stabilization of Cu(i) in aqueous solution (Patterson Holm, 1975). In a substantial study, the Cu(ii)/Cu(i) potentials and self-exchange electron transfer rate constants have been investigated for a number of copper complexes of cyclic poly-thioether ligands (Rorabacher et al., 1983). In all cases, these macrocycles produced the expected stabilization of the Cu(i) ion in aqueous solution. For a range of macrocyclic S4-donor complexes of type... 

In general, copper metal is extracted from its ores by various wet processes. These include leaching with dilute sulfuric acid or complexing with ligands (e.g., sahcylaldoximes), followed by solvent extraction. The solution is then electrolyzed to refine copper. 

As shown in Eq. 19.21. it is thought that this reaciion takes place through a dimeric, bridged intermediate of coordination number 5. Copper tends lo form a maximum of five reasonably strong bonds,60 so complexation with a nonlabile tetracoordinate macrocyclic ligand (NJ provides only one additional site for a sulfur ligand. The reaction in Eq. 19-21 is inhibited, and a thiolate complex can be isolated 6 ... 

Sulfur ligands, 633-655 coordination ability, 516 Sulfur monoxide metal complexes instability, 636 Superoxide dismutase, 773 copper complexes, 772 Superoxo complexes, 315-330 binuclear, 323, 325 reactions, 330 bridged... 

Figure 7. Ground-state wave function of plastocyanin. A HOMO wave function contour for plastocyanin (28). B HOMO wave function contour for the thiolate copper complex tet b (34/ C Copper L-edge (38) and sulfur K-edge (34) spectra as probes of metal-ligand covalency. D Absorption, single-crystal polarized absorption, and low-temperature MCD spectra of plastocyanin. The absorption spectrum has been Gaussian resolved into its component bands as in reference 33.

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