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

Preparation method of 2, 5-difluoro-4-nitrobenzoic acid

A technology of nitrobenzoic acid and difluorobenzene, which is applied in the field of preparation of 2,5-difluoro-4-nitrobenzoic acid, and can solve problems such as unseen

Inactive Publication Date: 2019-02-22
CHANGZHOU UNIV
View PDF2 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] At present, there is no relevant report on the synthesis method of 2,5-difluoro-4-nitrobenzoic acid

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 2, 5-difluoro-4-nitrobenzoic acid

Examples

Experimental program
Comparison scheme
Effect test

specific Embodiment approach 2

[0016] (1) Bromination reaction: Add 1000 g of p-difluorobenzene and 5000 mL of sulfuric acid into the reaction vessel, and control the temperature of the water bath to 30 °C. 1620 g of N-bromosuccinimide were added slowly with stirring. During the addition, the temperature should not exceed 40°C. After the addition, the reaction was incubated for 1 h, followed by GC until the end of the reaction. After the reaction, the reactant was poured into ice water to precipitate a solid, which was suction filtered to obtain 1568 g of light yellow powdery solid 2,5-difluorobromobenzene with a content of 98% and a yield of 92.7%.

[0017] (2) Nitration reaction: Add 1208 g of 2,5-difluorobromobenzene to the reaction vessel, add 5000 mL of concentrated sulfuric acid, control the temperature in an ice-water bath to about 5 degrees, then add 462 g of potassium nitrate, and keep warm for 1 h, GC trace until the end of the reaction. Water analysis in ice water, suction filtration, and dryi...

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 an industrial preparation method of 2, 5-difluoro-4-nitrobenzoic acid. According to the industrial preparation method of the 2, 5-difluoro-4-nitrobenzoic acid, p-difluorobenzene serves as an initial raw material, and the 2, 5-difluoro-4-nitrobenzoic acid is synthesized by bromination, nitration, cyaniding and hydrolysis four-step reaction. The 2, 5-difluoro-4-nitrobenzoic acid obtained in the process is off-white powdery solid with the purity of 98.5%, raw material conversion rate in each step reaches 100%, and the total yield of the whole process reaches 44.6%.

Description

technical field [0001] The invention relates to a production method of a pharmaceutical intermediate, in particular to a production method of 2,5-difluoro-4-nitrobenzoic acid. Background technique [0002] At present, 2,5-difluoro-4-nitrobenzoic acid is mainly used in the pharmaceutical industry. For example, it can be used for: 1) Synthesis of derivatives of metansinol and metansine for the treatment of cancer 2) Synthesis of indole carboxamide derivatives of p2x7 receptor antagonists 3) Synthesis of substituted benzimidazole compounds as COT kinase inhibitors to treat inflammation and Diseases such as cancer 4) Synthesis of thiadiazole compounds as protein kinase B regulators. [0003] At present, there is no relevant report on the synthesis method of 2,5-difluoro-4-nitrobenzoic acid. Therefore, it is necessary to develop a synthetic route suitable for industrial production. Contents of the invention [0004] The object of the present invention is to provide a method ...

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): C07C205/58C07C201/12C07C25/13C07C17/12C07C205/12C07C201/08C07C255/50C07C253/14
CPCC07C201/12C07C17/12C07C201/08C07C253/14C07C25/13C07C205/12C07C255/50C07C205/58
Inventor 陈兴权董燕敏
Owner CHANGZHOU UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com