N-(2-nitro-4-(trifluoromethyl)phenyl)acetamide (109.5 g, 0.5 mol) was used as a raw material and was mixed with 94% sulfuric acid solution (171.5 g) at a stirring rate of 550 rpm, and the reaction temperature was controlled to be 28 °C. Subsequently, 98% nitric acid solution (32.5 g, 0.51 mol) was added dropwise to the mixture at a dropwise acceleration rate of 40 g/min. After the dropwise addition, the nitrification reaction was continued for 2 hours. After completion of the reaction, the reaction system was heated to 80°C and the deacetylation reaction was carried out for 5 hours to obtain the deacetylated product. The deacetylation product was cooled to below 45°C and slowly added to ice water to precipitate the solid. The resulting solid was filtered and washed, followed by alkaline washing with 10% aqueous sodium hydroxide solution until the pH of the filtrate reached 7, terminating the alkaline washing process. The alkali washed solid was dried at 55 °C for 4.5 h. 104 g of 4-trifluoromethoxy-2-nitroaniline was finally obtained, which was analyzed by GC with a purity of 98.5% and a yield of 94%.
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