Synthesis Of 1-amino-8-naphthol-3, 6-disulfonic Acid

1-amino-8-naphthol-3,6-disulfonic acid is an important intermediate used for synthesizing some dyestuffs and pharmaceuticals.A total synthesis of 1-amino-8-naphthol-3,6-disulfonic acid monosodium salt starting from naphthalene, followed by sulfonic, reduction, nitration and reduction etc. was studied.The total yield was improved to 34.0% in a purity of 99.2%. Compared to traditional technology the reaction condition of the new technology was more convenient and mild.Naphthalene was sulfonated by excessive sulfuric acid. The different sulfonates content were analyzed in different reaction steps in order to optimize the conditions of reaction. Naphthalene-2,7-disulfonic acid was nitrated by nitric acid in the presence of acetic anhydride. The different Catalytic Hydrogen Transfer reducing agents was used to reduce the nitryl and the effect of the three Catalytic Hydrogen Transfer reducing agents was compared. The technological parameters were optimized, and related reaction mechanisms were investigated. The structures and compositions of these compounds were characterized by spectral analysis and chromatographic analysis.