1. In nature, anthranilic acid methyl ester exists in tahua oil, Neroli oil, jasmine oil, tuberose oil, etc. Generally, industrial production is obtained by esterification of o-aminobenzoic acid and methanol. The methanol solution of anthranilic acid methyl ester was heated to 65 ℃, and sulfuric acid was added dropwise, then the sulfuric acid of o-aminobenzoic acid methyl ester was formed at 75 ℃. Then the methyl o-aminobenzoate was neutralized with sodium hydroxide solution. After extraction with toluene, washing the toluene extraction liquid and steaming the toluene, the crude methyl o-aminobenzoate is rectified under the condition of sodium carbonate, and the finished product fraction is cooled to below 12-15℃, that is to say, methyl o-aminobenzoate is separated out. Another method is to get the product by ammoniation, degradation and esterification of phthalic 2. It is prepared by esterification of o-aminobenzoic acid and methanol in acid condition and neutralization in alkali. Or by the amination, degradation and esterification of phthalic anhydride. 3. Tobacco: Bu, 14.
2. With o-aminobenzoic acid as raw material, 3-hydroxyindazole (3-hydroxyindazole) o-aminobenzoic acid can be obtained by salification, diazotization, reduction and cyclization. When it is used to produce anthranilic acid methyl ester, 925kg per ton of product is consumed. In the production of indigo, 1495 kg o-aminobenzoic acid is needed.
3. The sodium o-carbamate is formed by the amidation of phthalic anhydride and ammonia. The sodium o-aminobenzoate is formed by the degradation of sodium hypochlorite, and finally neutralized. The consumption quota of raw materials is 1340kg/T of phthalic anhydride (melting point 128-131℃), 6484kg/T of sodium hypochlorite (effective chlorine ≥ 10%), 2350kg/T of ammonia water (≥16%), 2924kg/T of liquid alkali (30%).