| 摘要 |
A process for preparation of Fipronil (i.e. 5-amino-l-(2, 6-dichloro-4-trifluoromethylphenyl)-3-cyano-4-trifluoromethylsulphinyl-pyrazole) is provided, which comprises oxidizing 5-amino-l-(2, 6-dichloro-4-trifluoromethylphenyl)-3-cyano-4-trifluoromethylthio-pyrazole with sulfuric acid and hydrogen peroxide as oxidizing agent in the presence of a solvent such as ethylene dichloride, chlorobenzene. |
