Preparation method of triclabendazole

A technology of triclabendazole and preparation steps, which is applied in the field of preparation of triclabendazole, and can solve problems such as environmental pollution, unsuitability for industrial production, difficulty in filtering iron sludge, etc.

Active Publication Date: 2013-10-23
CHANGZHOU JIALING MEDICINE IND
View PDF2 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This is reported in detail in Chinese patent ZL200910027417.6. This route uses 2,3-dichlorophenol, which is easy to sublimate and has strong allergenicity, as a starting material. Special protection is required in the production process. At the same time, this scheme uses iron Powder is used as a reducing agent, and a large amount of iron sludge that is difficult to filter wi

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 triclabendazole
  • Preparation method of triclabendazole
  • Preparation method of triclabendazole

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0019] Embodiment 1: The preparation steps of triclabendazole according to the present invention are as follows:

[0020] The first step, the preparation of 4-chloro-5-(2,3-dichlorophenoxy)-2-nitroaniline, that is, the compound III in the reaction formula:

[0021] Add 43.5kg of 1,2,3-trichlorobenzene and 40kg of 50% potassium hydroxide aqueous solution into the reaction kettle, heat and reflux for 7 hours, then add 150L of xylene and 41.4kg of 4,5-dichloro-2-nitroaniline React with 5 kg of catalyst TBAB for 8 hours, the reaction temperature is controlled at 125 ° C, slowly cooled to room temperature under stirring, a large number of brownish yellow crystals are precipitated, filtered, washed with 10 kg of frozen xylene, drained, washed with water until neutral, and dried to obtain 4-Chloro-5-(2,3-dichlorophenoxy)-2-nitroaniline 54kg, yield: 81%, melting point: 145°C-150°C, the spectrum of this substance is as follows figure 1 Shown; Wherein, 1,2,3-trichlorobenzene is the com...

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 synthesizing triclabendazole by taking 1,2,3-trichlorobenzene as a raw material. The triclabendazole is generated through three steps by taking the 1,2,3-trichlorobenzene as a starting raw material. The method has the advantages that the inexpensive 1,2,3-trichlorobenzene is used as the starting raw material, and expensive 2,3-dichlorophenol with strong sensitization is not used. The 1,2,3-trichlorobenzene is hydrolyzed in high-concentration alkali liquor to prepare 2,3-dichlorophenol sodium which reacts with 4,5-dichloro-2-nitroaniline in a methylbenzene aqueous solution, and free 2,3-dichlorophenol is not generated again, so that the reaction yield is improved, and pollutions generated during production are avoided. The 4-chloro-5-(2,3-dichlorophenoxy)-2-nitroaniline is reduced by adopting a hydrogen catalytic transfer method, so that a large amount of iron mud which is difficult to treat and pollutes the environment is not generated; and an adopted hydrogen donator is low in price and does not cause any pollution to the environment, so that the triclabendazole is suitable for large-scale industrial production.

Description

technical field [0001] The invention relates to veterinary medicine triclabendazole, in particular to a preparation method of triclabendazole. Background technique [0002] At present, the effective insecticide used for ruminants such as cattle, sheep and goats is triclabendazole. According to the retrieval of patent literature and scientific literature, the existing synthesis techniques of triclabendazole mainly include the following two types: [0003] The first method: using 2,3-dichlorophenol and 4,5-dichloro-2-nitroaniline as raw materials, condensation reaction to obtain 2-amino-4-chloro-5-(2,3-dichloro phenoxy)-nitrobenzene, through a two-step reductive ring-closure reaction to obtain 5-chloro-6-(2,3-dichlorophenoxy)-2-mercapto-benzimidazole, and then with dimethyl sulfate Methylation reaction produces triclabendazole. This is reported in detail in Chinese patent ZL200910027417.6. This route uses 2,3-dichlorophenol, which is easy to sublimate and has strong allergen...

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): C07D235/28
Inventor 张月亮徐立新
Owner CHANGZHOU JIALING MEDICINE IND
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