Study On Synthesis And Application Of 1,2,4,5-tetraaminobenzene

In this paper,a method for the prepraation of large-scale engineering fiber monomer 1,2,4,5-tetraaminobenzene(TAB)is studied,and the synthesis process is systematically analyzed and optimized.Using the principle of quantum chemistry,the ammonia and hydrogenolysis reactions in the synthesis route were simulated.Among them,the aminolysis reaction is achieved by searching for aminolysis of 4,6-dinitro-1,2,3-trichlorobenzene at the(U)BLYP/6-311++G(2d,p)level.The possible transition states,and draw the activation energy barrier map of the compound,and then determine whether this step reaction can proceed smoothly.Observe the activation energy barrier diagram and find that the energy of the reactant to the transition state TS1(product)is 21.96 kcal/mol,the energy of the reactant to the transition state TS2(byproduct)is 35.14 kcal/mol,TS1 is smaller than TS2,so this step reaction can be realized.The hydrogenolysis reaction mainly uses the Geometry Optimization and Single point energy in the DMol~3 module for geometric optimization and single point energy calculation to obtain the optimized energy value of the compound,thereby judging whether the structure of the obtained compound is stable or not.It was found that after optimization 4 times,its energy value was stable,which was-453.68 Hartree,and the structure of the compound was stable.The 1,2,3-trichlorobenzene by-product of chlorinated benzene as raw material in the mixed acid nitrification 4,6-dinitro-1,2,3-trichlorobenzene(1),and then aminolysis to obtain4,6-dinitro-2-chloro-1,3-diaminobenzene(2),and finally obtain the target product 1,2,4,5-tetraaminobenzene(3)by catalytic hydrogenolysis,a total yield of 77.6%of was obtained.The main product was been conducted a comprehensive characterization by the means of the means of mp,IR,1H-NMR.The results indicated that the product structure was correct.The advantage of this synthetic route is simple operation,using chlorinated benzene as a starting material to turn waste into treasure,with high product yield and fewer by-products,which is conducive to industrial production.