Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Method for synthesizing 2, 5-dichloro-phthaldialdehyde

A technology of dichloroterephthalaldehyde and dichloro-p-xylene, applied in two fields, can solve problems such as low yield, unreported synthesis method, corrosion pollution, etc., achieve short reaction route, low cost, and easy operation Effect

Inactive Publication Date: 2010-01-20
XUZHOU HUARI CHEM IND
View PDF2 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] At present, the production of terephthalaldehyde in China is mainly based on the hydrolysis of benzylidene dichloride, the yield is not high, the corrosion pollution is serious, and it needs to be improved and replaced.
[0004] 2,5-dichloroterephthalaldehyde is a new type of compound, and its synthetic method has not been reported

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
  • Method for synthesizing 2, 5-dichloro-phthaldialdehyde

Examples

Experimental program
Comparison scheme
Effect test

specific Embodiment approach

[0020] The present invention will be further described below in conjunction with specific examples, but the present invention is not limited to these specific examples.

example 1

[0022] Preparation of 2,5-dichloro-p-xylene: Add 200g of acetic acid, 2.3g of antimony trichloride and 21.3g of p-xylene into a 500ml round bottom flask. Heat and stir, control the temperature at 20-40°C, and control the chlorine flow rate by bubbling. Keep the reaction below 40°C, continue to pass chlorine for 2 to 4 hours, and the reaction solution is yellow-green. Recrystallization gave 34.1 g of 2,5-dichloro-p-xylene (melting point: 69-70°C, yield: 97.5%).

[0023] The preparation of 2,5-dichloroterephthalaldehyde: add 35g 2,5-dichloro-p-xylene in 220ml acetic acid, heat and stir until fully dissolved, then add 300ml70% sulfuric acid solution, add 80g manganese dioxide in batches, Continue to raise the temperature to reflux, react for 8 hours, filter out the insoluble matter, extract, wash, dry, and distill under reduced pressure to collect 34.8g of the fraction product at 183-187°C under 0.005MPa, which is 2,5-dichloro-terephthalene Formaldehyde (melting point 157-158°C...

example 2

[0025] Preparation of 2,5-dichloro-p-xylene: Add 200g of acetic acid, 2.6g of antimony trichloride and 21.3g of p-xylene into a 500ml round bottom flask. Heat and stir, control the temperature at 20-40°C, and control the chlorine flow rate by bubbling. Keep the reaction at no more than 40°C, continue to pass chlorine for 5 hours, and the reaction solution is yellow-green. Recrystallization gave 34.4 g of 2,5-dichloro-p-xylene (melting point: 69-70°C, yield: 98.1%).

[0026] Preparation of 2,5-dichloroterephthalaldehyde: add 35g 2,5-dichloro-p-xylene to 100ml acetic acid, heat and stir until completely dissolved, then add 250ml 70% sulfuric acid solution, add 74g manganese dioxide in batches , continue to heat up to reflux, react for 5 to 7 hours, filter out insoluble matter, extract, wash, dry, and distill under reduced pressure to collect 35.2 g of the fraction product at 183 to 187 °C under 0.005 MPa, which is 2,5-dichloro Terephthalaldehyde (melting point 157-158°C, yield...

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 relates to a method for synthesizing 2, 5-dichloro-phthaldialdehyde, which is characterized by comprising the following steps: paraxylene and chlorine gas are catalyzed by using antimony trichloride in glacial acetic acid and react to generate 2, 5-dichloro-paraxylene; then, manganese dioxide is used for oxidizing the 2, 5-dichloro-paraxylene in the mixed solution of acetic acid and concentrated sulfuric acid, and the 2, 5-dichloro-phthaldialdehyde is obtained by extraction and depressurized distillation. The invention has the characteristics of short synthetic route, simple and convenient operation, low cost and easy industrialization.

Description

technical field [0001] The invention belongs to the technical field of organic synthesis, and relates to an organic synthesis method of 2,5-dichloroterephthalaldehyde. Background technique [0002] Terephthalaldehyde is an important intermediate in organic synthesis and polymer synthesis. It has two active aldehyde groups, so it can not only self-polymerize, but also copolymerize with other monomers to form compounds with various properties. Terephthalaldehyde is an important intermediate in the preparation of spices, dyes, medicines, plastics, fluorescent whitening agents, etc. It not only has a large export demand, but also has a considerable domestic demand. [0003] At present, the production of terephthalaldehyde in China is mainly based on the hydrolysis of benzylidene dichloride, the yield is not high, the corrosion pollution is serious, and it needs to be improved and replaced. [0004] 2,5-Dichloroterephthalaldehyde is a new type of compound, and its synthesis meth...

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): C07C47/55C07C45/28B01J27/10
Inventor 牟杰李鹏刘晔王永章朱新春王家森
Owner XUZHOU HUARI CHEM IND
Features
  • Generate Ideas
  • Intellectual Property
  • Life Sciences
  • Materials
  • Tech Scout
Why Patsnap Eureka
  • Unparalleled Data Quality
  • Higher Quality Content
  • 60% Fewer Hallucinations
Social media
Patsnap Eureka Blog
Learn More

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

© 2025 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com