3-Amino-5--trifluoromethyl--1H-pyraz 1028843-19-7

Chemical properties the pure product is white crystal solid, the industrial product is light yellow brown solid, m.p.141 ~ 142℃, soluble in methanol, ethanol, acetone, dichloroethane and ethyl acetate. Use 5- amino -3- cyanogen -1-(2,6 - dichloro -4- trifluoromethyl phenyl) pyrazole for short pyrazole, is the insecticide fluorobenzene intermediate. The preparation method is using 2, 6-dichloro-4-trifluoromethyl aniline as raw material, and the diazo salt is obtained by diazotization reaction. The diazo salt is condensation with ethyl dichloropropionate and then passes through the ring closure to obtain pyrazole (2, 6-dichloro4-trifluoromethyl phenyl). Sulfuric acid and solvent were added in the reaction bottle, and sodium nitrite was added in batches under agitation. After the addition, the mixture was stirred for 30min, and the diazonium salt of 2, 6-dichloro-4-trifluoromethyl aniline was obtained by dropping 2, 6-dichloro-4-trifluoromethyl aniline at 20 ~ 40℃ and stirring for 1h. Add water in the diazonium salt and 2, 3-2 cyano propionic acid ethyl ester, stirring at room temperature 2 h, to join the methylene chloride, stir well, after the material transferred to the separatory funnel, separated layer, then use methylene chloride extraction, merger of methylene chloride liquid, water washing, reoccupy dilute alkaline cleaning to pH = 9, moving reaction bottle, add ammonia, stirring at room temperature 2 h after stratification, water layer with methylene chloride extraction, merger of methylene chloride layer, and washed to neutral, steamed to methylene chloride products.