Patent ID: 8188317
Filing Date: 2012-05-29
Classification: C07C,Y02P

Abstract:
1. An integrated process for preparing an isolated complex of 2,3,5,6-tetraminotoluene and the aromatic diacid XYTA, wherein the complex is 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) nitrating 2,6-dihalotoluene (II) b) directly separating the 2,6-dihalo-3,5-dinitrotoluene from the reaction mixture by filtration, while recycling the sulfuric acid mother liquor; c) washing the 2,6-dihalo-3,5-dinitrotoluene with water or acid then water, then with NH d) aminating the 2,6-dihalo-3,5-dinitrotoluene by heating the suspension formed in step (c) to a temperature in the range of about 100° C. to about 160° C. and contacting it with NH e) directly separating the 2,6-diamino-3,5-dinitrotoluene from the reaction mixture by filtration, washing with glycol, then washing with water; f) forming a slurry of the 2,6-diamino-3,5-dinitrotoluene with water and transferring the slurry to a hydrogenation reactor containing a hydrogenation catalyst to form a reaction mixture; g) hydrogenating the 2,6-diamino-3,5-dinitrotoluene by contacting the reaction mixture formed in step (f) with hydrogen at a pressure in the range of about 0.31 to about 3.45 MPa and a temperature in the range of about 20° C. to about 100° C. to hydrogenate the 2,6-diamino-3,5-dinitrotoluene, thereby producing 2,3,5,6-tetraminotoluene; h) contacting the 2,3,5,6-tetraminotoluene produced in (a) with an aqueous solution comprising 1 to 6 equivalents of acid per mol of 2,3,5,6-tetraminotoluene, optionally heating the solution, thereby dissolving the 2,3,5,6-tetraminotoluene; i) filtering the reaction mixture, thereby removing the spent hydrogenation catalyst; j) combining the filtered reaction mixture with k) cooling, filtering, and washing the isolated and precipitated complex.