Preparation method of benzoylurea anthelmintic

A technology for benzoyl urea and anthelmintic medicine, which is applied in the field of preparation of benzoyl urea anthelmintic medicine, can solve problems such as high toxicity, and achieve the effects of simplifying post-processing and avoiding oxidation by-products.

Pending Publication Date: 2022-07-29
CHANGZHOU YABANG QH PHARMACHEM +1
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In addition, in the preparation process, dichloromethane, the first-class toxic substance stipulated by WHO, is used, and its residue limit is 5ppm. For the preparation of veterinary drugs, the use of dichloromethane as a solvent is too toxic, and there is a problem of drug safety.

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 benzoylurea anthelmintic
  • Preparation method of benzoylurea anthelmintic
  • Preparation method of benzoylurea anthelmintic

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0041] To a 500ml four-necked flask, add 300ml of p-xylene, 2,5-dichloro-4-(1,1,2,3,3,3-hexafluoropropoxy) nitrobenzene is 35.8g (0.1mol) , 0.2g of ferric oxyhydroxide and 0.8g of activated carbon, start stirring, heat up to 65 ° C, add 10.5 g of hydrazine hydrate dropwise, control the temperature to 65-69 ° C, and drop the time for 0.5 hours. To 25-30 ℃, stand, separate the lower water layer, wash the organic layer with 1 times the amount of water, separate the lower water layer to obtain the reduced product 2,5-dichloro-4-(1,1,2,3 , 3,3-hexafluoropropoxy) aniline in p-xylene.

[0042]16.5g (0.105mol) of 2,6-difluorobenzamide and 66g of p-xylene were added to the 500ml reaction flask, the temperature was raised to 25°C with stirring, 19.0g (0.15mol) of oxalyl chloride was slowly added dropwise, and the reaction temperature was controlled to 35°C , the dropping time was 1 hour, and the temperature was raised to 110 ° C after the dropping was completed for 1 hour. After the re...

Embodiment 2

[0048] To a 500ml four-necked flask, add 200ml of o-xylene, 2,5-dichloro-4-(1,1,2,3,3,3-hexafluoropropoxy) nitrobenzene is 35.8g (0.1mol) , 0.7g of ferric chloride and 1.0g of activated carbon, turn on stirring, heat up to 65 ° C, dropwise add 18.5 g of hydrazine hydrate, control the temperature to be 65-69 ° C, and drop the time for 1 hour, after dropping the insulation reaction for 1 hour, cooling down To 25-30 ℃, stand, separate the lower water layer, wash the organic layer with 1 times the amount of water, separate the lower water layer to obtain the reduced product 2,5-dichloro-4-(1,1,2,3 , 3,3-hexafluoropropoxy) aniline solution in o-xylene.

[0049] Add 16.5g (0.105mol) of 2,6-difluorobenzamide and 120g of o-xylene to the 500ml reaction flask, stir and heat up to 25°C, slowly add 21.5g (0.17mol) of oxalyl chloride dropwise, and control the reaction temperature to 25°C , the dropping time is 1 hour, and the temperature is raised to 112° C. after the dropwise addition is...

Embodiment 3

[0054] To a 500ml four-necked flask, add 320ml of toluene, 2,5-dichloro-4-(1,1,2,3,3,3-hexafluoropropoxy) nitrobenzene is 35.8g (0.1mol), hydrogen 0.5g of bismuth oxide and 1.2g of activated carbon, turn on stirring, heat up to 65°C, add 12.5g of hydrazine hydrate dropwise, control the temperature to be 65-69°C, add dropwise time for 0.5 hour, finish the dripping for 3 hours, and cool down to 25 -30℃, stand still, separate the lower water layer, wash the organic layer with 1 times the amount of water, separate the lower water layer to obtain the reduced product 2,5-dichloro-4-(1,1,2,3,3 , 3-hexafluoropropoxy) aniline in toluene.

[0055] 17.2g (0.11mol) of 2,6-difluorobenzamide and 70g of toluene were added to the 500ml reaction flask, the temperature was raised to 25°C with stirring, and 17.3g (0.14mol) of oxalyl chloride was slowly added dropwise, and the reaction temperature was controlled at 30°C. Add time for 1 hour, be incubated for 1 hour after the dropwise addition is...

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

PropertyMeasurementUnit
melting pointaaaaaaaaaa
melting pointaaaaaaaaaa
melting pointaaaaaaaaaa
Login to view more

Abstract

The invention discloses a preparation method of a benzoylurea anthelmintic. The preparation method comprises the following steps: by taking 2, 5-dichloro-4-(1, 1, 2, 3, 3, 3-hexafluoropropoxy) nitrobenzene and 2, 6-difluorobenzamide as initial raw materials, reducing the 2, 5-dichloro-4-(1, 1, 2, 3, 3, 3-hexafluoropropoxy) nitrobenzene through hydrazine hydrate, reacting the 2, 6-difluorobenzamide with oxalyl chloride to generate isocyanate, and finally performing amidation reaction to obtain the lufenuron. The invention provides the preparation method of the veterinary drug lufenuron, which is green, environment-friendly, mild in reaction, less in side reaction, short in synthetic route, simple and convenient to operate and high in purity, the same green solvent is adopted, high-toxicity dichloroethane is not used as a solvent, post-treatment is simplified, and oxidation byproducts are prevented from being generated in the high-temperature distillation process of the reduzate. A mild hydrazine hydrate reduction method is adopted, so that propoxy bond breakage and dechlorination impurities generated by catalytic hydrogenation reduction are avoided, and then impurities B and C are generated in a finished product. The purity of the prepared lufenuron impurity can reach 99.8% or above, and the yield reaches 86.0% or above.

Description

technical field [0001] The invention belongs to the field of chemistry or medicinal chemistry, and in particular relates to a preparation method of a benzoylurea anthelmintic. Background technique [0002] Benzoyl urea anthelmintics, the main ingredient is benzoyl urea compounds (BU), is a class of insect growth regulators (IGRs) that can inhibit the synthesis of chitin in target pests and cause their death or sterility, Known as the third-generation pesticides or new insect control agents. Benzoyl ureas have become an active field in the creation of new pesticides, and have received extensive attention due to their attractive properties such as unique mechanisms of action, high environmental safety, and broad-spectrum and high-efficiency insecticidal activities. Benzoyl urea anthelmintics include imidacloprid, fendiuron, lufenuron and so on. [0003] Lufenuron is an insect chitin synthesis inhibitor and belongs to the benzoylurea class of insecticides. Lufenuron can be u...

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
Patent Type & Authority Applications(China)
IPC IPC(8): C07C273/18A01N47/34C07C275/54A01P7/02A01P7/04
CPCC07C273/1827A01N47/34C07C275/54
Inventor 朱建民王学成高新宇金叶峰符岩苏文杰
Owner CHANGZHOU YABANG QH PHARMACHEM
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