Synthesis of diaminodinitropyridine

Abstract

A process for the preparation of diaminodinitropyridine or diaminodinitrobenzene by contacting an aminopyridine or aminobenzene with oleum and nitric acid, wherein the improvement comprises adding at least about 1% molar excess of nitric acid, based upon the aminopyridine or aminobenzene, with stirring for at least two hours to form first the intermediate sulfonic acid, and then diaminodinitropyridine or diaminodinitrobenzene, and use of such products in the preparation of rigid rod polymers is disclosed.

1 - 13 . (canceled) 
     
     
         14 . A process for the preparation of poly(2,3,5,6-tetraaminopyridine-co-2,5-dihydroxyterephthalate) having an inherent viscosity of at least 25 dL/g comprising
 A) hydrogenation of diaminodinitropyridine which contains less than about 0.1% by weight of 2,6-diamino-3-nitropyridine-5-sulfonic acid to yield tetraaminopyridine,   B) coupling of said tetraaminopyridine with dipotassium dihydroxyterephthalate to yield a tetraaminopyridinium dipotassium dihydroxyterephthalate complex, and   C) polymerization of said tetraaminopyridinium dipotassium dihydroxyterephthalate complex to yield poly(2,3,5,6-tetraaminopyridine-co-2,5-dihydroxyterephthalate) having an inherent viscosity of at least 25 dL/g.   
     
     
         15 . The process of  claim 14  wherein the poly(2,3,5,6-tetraaminopyridine-co-2,5-dihydroxyterephthalate) has a tenacity of at least 35 g(force)/denier. 
     
     
         16 . The process of  claim 14  wherein the diaminodinitropyridine contains less than about 0.05% by weight of 2,6-diamino-3-nitropyridine-5-sulfonic acid. 
     
     
         17 . The process of  claim 14  wherein the diaminodinitropyridine contains less than about 1% by weight of 2-hydroxy-6-amino-3,5-dinitropyridine. 
     
     
         18 . A process for the preparation of poly(2,3,5,6-tetraaminobenzene-co-2,5-dihydroxyterephthalate) having an inherent viscosity of at least 25 dL/g comprising
 A) hydrogenation of diaminodinitrobenzene which contains less than about 0.1% by weight of 2,6-diamino-3-nitrobenzene-5-sulfonic acid to yield tetraaminobenzene,   B) coupling of said tetraaminobenzene with dipotassium dihydroxyterephthalate to yield a tetraaminobenzene dipotassium dihydroxyterephthalate complex, and   C) polymerization of said tetraaminobenzene dipotassium dihydroxyterephthalate complex to yield poly(2,3,5,6-tetraaminobenzene-co-2,5-dihydroxyterephthalate) having an inherent viscosity of at least 25 dL/g.   
     
     
         19 . The process of  claim 18  wherein the diaminodinitrobenzene contains less than about 0.05% by weight of 2,6-diamino-3-nitrobenzene-5-sulfonic acid.