Preparation method of fipronil

A technology of fipronil and trifluoromethyl phenyl is applied in the field of oxidizing 5-amino-3-cyano-1--4-trifluoromethylthiopyrazole to generate fipronil, which can solve the problem of expensive trifluorocarbon Acetic acid and trifluoroacetic acid cannot be directly applied, etc., to achieve the effects of simple process, good industrial application prospects and environmental friendliness

Active Publication Date: 2008-08-27
HUNAN CHEM RES INST
View PDF2 Cites 35 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

US6881848 discloses the preparation method of using hydrogen peroxide to oxidize and synthesize fipronil in a trifluoroacetic acid medium; its d

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Preparation method of fipronil
  • Preparation method of fipronil

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0015] Under cooling, add 40 grams of 5-amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-trifluoromethylthiopyrazole, 200ml of three-necked flask Methyl chloride, stir for 20 minutes, add 40 grams of 118% sulfuric acid, 1 gram of tetrabutylammonium chloride, slowly add 16 grams of 30% hydrogen peroxide, control the temperature -10~-5℃, and react at this temperature 5 After ~6 hours, sample and monitor. After the reaction is completed, 120ml of water is added dropwise at 0~4℃, and the layers are separated. The organic layer was washed with saturated sodium bicarbonate solution until it was neutral, separated into layers, desolvated, and dried to obtain 39.2 g of fipronil technical.

Embodiment 2

[0017] Under cooling, 24 grams of sodium perborate and 0.4 grams of tetrabutylammonium bromide were slowly added to 80 grams of 96% sulfuric acid, stirred for 20 minutes, and 40 grams of 5 dissolved in 200 ml of dichloromethane were added dropwise at 0-4°C. -Amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-trifluoromethylthiopyrazole, and react at this temperature for 2 to 3 hours, and sample After monitoring, after the reaction is completed, 80 ml of water is added dropwise at 0-4°C, and the layers are separated. The organic layer was washed with saturated sodium bicarbonate solution to neutrality, separated into layers, desolvated, and dried to obtain 39.3 g of fipronil technical.

Embodiment 3

[0019] Under cooling, 20 grams of sodium perborate and 1 gram of 4-N,N-lutidine were slowly added to 400 grams of 60% sulfuric acid, stirred for 20 minutes, and then added dropwise to 50 ml of carbon tetrachloride at 10°C. 40 grams of 5-amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-trifluoromethylthiopyrazole, and react at this temperature for 6-8 After the reaction is completed, 60ml of water is added dropwise at 10°C, and the layers are separated. The organic layer was washed with saturated sodium bicarbonate solution to neutrality, separated into layers, desolvated, and dried to obtain 39.4 g of fipronil technical.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a method for using 5-amino-3-cyano-1-(2, 6-dichloro-4-trifluoromethylphenyl)-4-Trifluoromethylthio pyrazole as raw material to generate fipronil via catalysis and oxidation in solvent and sulfate medium. The chemical equation is represented as above. The invention oxidizes sulfate medium to generate fipronil, and the sulfate can be diluted by adding water and be layered to recover. The invention has the advantages of simple process, environment protection, mild reaction conditions and low production cost, with wide industrial application.

Description

Technical field [0001] The present invention relates to a preparation method of fipronil, in particular to 5-amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-trifluoromethyl sulfide The method of generating fipronil by oxidation of pyrazole. Background technique [0002] Fipronil, also known as fipronil, chemical name 5-amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)-4-trifluoromethylsulfinyl Pyrazole. White solid, melting point 200-201°C. Vapor pressure 3.7×10 -4 MPa (25°C), solubility: water 2 mg / l, acetone>50%. Acute oral LD ​​in rats 50 It is 97 mg / kg. Fipronil is a broad-spectrum insecticide with touch, stomach toxicity and moderate systemic effects. It can control underground pests and above ground pests. The main targets include aphids, leafhoppers, lepidopteran larvae, Pests such as flies and coleoptera. The preparation method of fipronil described in EP0295117 is synthesized from 5-amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)pyrazole and trifl...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): C07D231/44A01P7/00
Inventor 陶贤鉴黄超群熊莉莉罗亮明
Owner HUNAN CHEM RES INST
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap