Preparation method of 5-amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl) pyrazole disulfide

Abstract

The invention discloses a preparation method of 5-amino-3-cyano-1-(2, 6-dichloro-4-trifluoromethylphenyl)pyrazole disulphide, and belongs to the technical field of medicines. The preparation method comprises the steps of dissolving 5-amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)pyrazole in a mixed solvent, reducing the temperature, dropwise adding sulfur monochloride, increasing the temperature, conducting heat preservation for a halogenation reaction in a mixed solvent to generate 5-amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)pyrazole disulfide; conducting first separation and purificationon the reaction liquid of the halogenation reaction, recycling the mixed solvent, and leaving a residue; performing secondary separation and purification on the residue to obtain a crude product; and subjecting the crude product to third separation and purification to obtain a 5-amino-3-cyano-1-(2, 6-dichloro-4-trifluoromethylphenyl)pyrazole disulfide refined product. Operation is simplified, the generation efficiency is improved, the adverse effect of the characteristics of high polarity and easy water absorption of acetonitrile on the reaction is avoided, and the operation difficulty is reduced.

Description

【Technical field】 [0001] The invention relates to the technical field of medicine, in particular to a preparation method of 5-amino-3-cyano-1-(2,6-dichloro-4-trifluoromethyl-phenyl)pyrazole disulfide. 【Background technique】 [0002] 5-Amino-3-cyano-1-(2,6-dichloro-4-trifluoromethyl-phenyl)pyrazole disulfide was developed by the French Rhone-Planck company, an insecticidal Fipronil is an intermediate of the agent fipronil. Fipronil is a phenylpyrazole insecticide with a wide insecticidal spectrum. It hinders the metabolism of chlorine compounds controlled by insect γ-aminobutyric acid, so it has high insecticidal activity against important pests such as aphids, leafhoppers, planthoppers, Lepidoptera larvae, flies and Coleoptera, and has no phytotoxicity to crops . The agent can be applied to the soil or sprayed on the leaves. When applied to the soil, it can effectively prevent and control corn root beetles, needleworms and cutworms. Effective and long-lasting. [0003] A...

AI Technical Summary

Problems solved by technology

[0005] This technical route uses a mixed solvent of chlorobenzene and acetonitrile as the reaction solvent, and after the reaction is completed, liquid ammonia is used to neutralize the residual hydrogen chloride in the reaction system; It is very large; and the reaction uses a mixed solvent of acetonitrile and chlorobenzene, wherein the polarity of acetonitrile is relatively large, and the recovery process is easier to absorb water, but the reaction has higher requirements for water, and the solvent recovery is difficult, which is not conducive to industrial production

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