Patent ID: 8163961

Claim:
A process for preparing a complex generally described by Formula I wherein X and Y are each independently selected from the group consisting of H, OH, SH, methyl, ethyl, F, Cl, and Br; comprising the sequential steps under exclusion of oxygen: a. contacting 2,3,5,6-tetraaminotoluene (Formula II) with an aqueous solution comprising 1 to 6 equivalents of acid per mol of 2,3,5,6-tetraaminotoluene, optionally heating the solution, thereby dissolving the 2,3,5,6-tetraaminotoluene; b. combining the dissolved 2,3,5,6-tetraaminotoluene with i. 0 to 5 equivalents of an acid; ii. 0 to 5 equivalents of an organic base or an inorganic base; iii. optionally, a buffer solution; and iv. an XYTA source selected from XYTA and M 2 XYTA (Formula III) wherein M is K or Na, and wherein the molar ratio of XYTA to the 2,3,5,6-tetraaminotoluene salt is from 1:1 to 1:1.1; thereby adjusting the pH of the mixture to between about 3 and about 10 and thereby producing and precipitating the complex generally described by Formula (I); and c. cooling, filtering, and washing the precipitated complex.