Method for preparing high-purity 1,2-dimethyl-3-phenylpyrazoline chlorate by utilizing industrial waste 1,2-dimethylhydrazine as raw material

A technology of phenylpyrazoline chlorate and dimethylhydrazine, which is applied in the field of preparation of high-purity 1, can solve problems such as environmental pollution and waste of resources, and achieve cost reduction, product stability improvement, and simple and easy-to-operate equipment Effect

Active Publication Date: 2019-07-05
DONGLI NANTONG CHEM +1
View PDF1 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0008] The present invention solves the problem that the by-product 1,2-dimethylhydrazine in the industrial waste discharged during the synthesis of monomethylhydrazine can be fully utilized, and avoids environmental pollution and waste of resources caused by such dangerous compounds. Waste liquid can better realize the problem of turning waste into treasure, and invented a method of using industrial waste containing by-product 1,2-dimethylhydrazine in the production process of monomethylhydrazine to realize it through the conventional mannich reaction

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0014] Add 1,2-dimethylhydrazine 60g (1mol), 120g acetophenone (1mol), 30g formaldehyde (1mol) and 300ml Mix with absolute ethanol, then heat the reaction mixture at the same temperature until 1,2-dimethyl-5-phenylpyrazoline is formed, acidify by adding appropriate 70% perchloric acid dropwise, cool and filter to obtain a brown solid, wash, The crude product was recrystallized with ethanol, suction filtered, and vacuum-dried at 60°C to obtain a yellow powder, 222g, with a yield of 81.1% and a purity of 95.4%.

Embodiment 2

[0016] In a three-necked round-bottomed flask equipped with a mechanical stirrer, dropping funnel and reflux condenser, take 60g (1mol) of 1,2-dimethylhydrazine, add a small amount of benzaldehyde-acetone mixture, stir and warm for 20min, add 120g of benzene Ethanone (1mol), 30g formaldehyde (1mol), a small amount of citric acid and 300ml isopropanol are mixed, then the reaction mixture is heated at the same temperature until 1,2-dimethyl-3-phenylpyrazoline is formed, dropwise Add appropriate 70% perchloric acid to acidify, cool and filter to obtain a white solid, wash, recrystallize the crude product with isopropanol, suction filter, and vacuum dry at 60°C to obtain a white crystalline powder. The product is 258g, with a yield of 94.3% and a purity of 99.4%. .

Embodiment 3

[0018] In a three-neck round-bottomed flask equipped with a mechanical stirrer, dropping funnel and reflux condenser, take 60g (1mol) of 1,2-dimethylhydrazine, add a small amount of acetic anhydride acetone solution, stir and warm for 20min, add 120g of styrene Ketone (1mol), 30g formaldehyde (1mol), a small amount of tert-butyl hydrodiphenol and citric acid, add 300ml isopropanol and mix, then heat the reaction mixture at the same temperature until 1,2-dimethyl-5-benzene Add appropriate 70% perchloric acid dropwise to acidify and cool and filter to obtain a white solid, wash, recrystallize the crude product with isopropanol, filter with suction, and dry under vacuum at 60°C to obtain a white crystalline powder. 256g of the product is obtained. Yield 93.7%, purity 99.5%.

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 provides a method for preparing high-purity 1,2-dimethyl-3-phenylpyrazoline chlorate by utilizing industrial waste 1,2-dimethylhydrazine as a raw material. The 1,2-dimethyl-3-phenylpyrazoline chlorate is an important medicine and pesticide intermediate. In order to accomplish and overcome the disadvantages of instability and more reaction by-products of hydrazine compounds, the method of adding a related impurity protecting agent and an antioxidant into the starting material before the reaction is adopted, a mannich reaction is carried out in a higher alcohol solvent to obtain the high-purity 1,2-dimethyl-3-phenylpyrazoline chlorate powdered crystal, and the method provided by the invention solves the problems of more types of finally residual target impurities and complicated purification steps in industrial production, solves the problems existing in a conventional method for preparing high-purity 1,2-dimethyl-3-phenylpyrazoline chlorate, controls and eliminates all impurity sources, and realizes the advantages of having commercial scale production, reducing costs, and having simple equipment.

Description

technical field [0001] The invention relates to the field of organic synthesis, in particular to a technical method for preparing high-purity 1,2-dimethyl-3-phenylpyrazoline chlorate by using industrial waste 1,2-dimethylhydrazine. Background technique [0002] my country is a big producer of monomethylhydrazine, and its annual output ranks among the top in the world. Monomethylhydrazine is a very valuable compound that is widely used in various industries such as medicine, pesticide, chemical industry, aerospace and missiles, and the production of this raw material is also increasing in large quantities with the large demand of the market. [0003] During the industrial preparation of monomethylhydrazine, by-products include 1,1-dimethylhydrazine and 1,2-dimethylhydrazine. The by-product of 1,1-dimethylhydrazine is separated and sold, which is an important raw material for the synthesis of rocket fuel and pharmaceutical intermediates. There is currently no known commercia...

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): C07D231/12
CPCC07D231/12
Inventor 阿依别克·马力克衣伟男周建
Owner DONGLI NANTONG CHEM
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