Synthesis method of 2-cyano-4-nitroaniline

The invention provides a synthesis method of 2-cyano-4-nitroaniline. The synthesis method comprises the following steps of: synthesizing 2-cyano-4-nitroaniline; the synthesis method comprises the following steps: a nitration step: 2-chlorobenzonitrile is dissolved in an organic solvent, a nitration reaction is carried out in the presence of mixed acid, a nitration product is obtained, and the nitration product contains 2-chloro-5-nitrobenzonitrile; a mixing step: mixing the nitration product with an inorganic solvent to obtain a mixed product; a separation step: standing and layering the mixed product to obtain an organic phase; ammonia gas and/or ammonia gas are/is introduced into the organic phase, an ammonolysis reaction is carried out, an ammonolysis product is obtained, and the ammonolysis product contains the 2-cyano-4-nitroaniline. According to the synthesis method, a large amount of sulfuric acid can be saved, and the used organic solvent can be recycled after the reaction is finished. Furthermore, th