Patent ID: 7449591

Claim:
A process for diminishing the concentration of a transition metal complex in a first solution containing said complex by the addition of a second solution, comprising the steps: (a) adding to the first solution a solubility-enhancing compound that enhances the solubility of said complex in the second solution; (b) combining the first solution with the second solution wherein the second solution is immiscible with the first solution; (c) mixing the first solution and second solution together; and, (d) removing the second solution from the first solution; wherein the solubility-enhancing compound is a compound of formula A wherein, R a is SH, or OH; R b is SH, or OH; R c each independently is H, SH, or OH; R d each is H; n is 1, 2, 3, or 4; or a salt or an activated form thereof.