Supercharge Your Innovation With Domain-Expert AI Agents!

A kind of method for preparing 2-chloronicotinic acid with 2,3-pyridinedicarboxylic acid as raw material

A technology of dipicolinic acid and chloronicotinic acid is applied in the field of production of pesticides and pharmaceutical products, can solve the problems of unsuitability for industrial production, long process route, easy volatility and the like, and achieves easy mass production and easy availability of raw materials. , Easy to operate effect

Active Publication Date: 2022-03-22
JIANGSU HANKUO BIOLOGICAL +1
View PDF7 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0014] The process route is long, the total yield is not high, there are many types of reagents used, it is difficult to recycle and apply mechanically, and there are hidden dangers in environmental protection; in addition, acrolein as the main raw material is relatively toxic and volatile, which brings more problems to production operations. Therefore, this process is not yet suitable for industrialized production (Mayer Joseph. Process for preparation 2-halogenonicotinic acids [P]. USP 4081451, 1978-03-28.)
[0015] In summary, there are not many routes for large-scale production of 2-chloronicotinic acid at present, and there are certain disadvantages. Therefore, it is necessary to develop a new 2-chloronicotinic acid preparation process with industrial production value is an urgent issue

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
  • A kind of method for preparing 2-chloronicotinic acid with 2,3-pyridinedicarboxylic acid as raw material
  • A kind of method for preparing 2-chloronicotinic acid with 2,3-pyridinedicarboxylic acid as raw material
  • A kind of method for preparing 2-chloronicotinic acid with 2,3-pyridinedicarboxylic acid as raw material

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] 16.7g (0.1mol) of quinolinic acid was added to 150ml of water, and 31.6g of KMnO was added in batches under stirring. 4 (0.2mol), slowly warming up to 85-90°C, keep feeding chlorine gas into the system at this temperature range, monitor the reaction by TLC after 1-1.5 hours until the raw materials disappear, and the reaction is complete;

[0036] Then add 3.0g activated carbon to the reaction solution and continue to stir for 0.5 hours to decolorize, perform hot filtration at 75°C, and cool the filtrate to room temperature, add 20% NaOH aqueous solution to adjust the pH value to 5, filter , and washed the filter cake with water to obtain 14.5 g of the product 2-chloronicotinic acid with a yield of 91% and a purity of 99.1%.

[0037] After testing, the melting range of the product is: 181-182°C;

[0038] MS (m / z): 157 (M+), 140, 112, 76, 50.

Embodiment 2

[0040] Add 16.7g (0.1mol) of quinolinic acid into 300ml of NaClO aqueous solution (mass percentage is 13%), slowly heat up to 85-90°C under stirring, keep this temperature and feed chlorine into the system, 1-1.5 Hours later, TLC monitors the reaction until the raw material disappears, and the reaction is complete;

[0041] Then add 3.0g activated carbon to the reaction solution and continue to stir for 0.5 hours to decolorize, perform hot filtration at 75°C, and cool the filtrate to room temperature, add 20% NaOH aqueous solution to adjust the pH value to 5, filter , washed the filter cake with water to obtain 11.8 g of the product 2-chloronicotinic acid with a yield of 74% and a purity of 99.2%.

[0042] After testing, the melting range of the product is: 181-182°C;

[0043] MS (m / z): 157 (M+), 140, 112, 76, 50.

Embodiment 3

[0045] 16.7g (0.1mol) of quinolinic acid was added to 300ml of chloroform, and 111g of Pb(OAc) was added in batches under stirring 4 (0.25mol), keep stirring and slowly heat up to reflux, feed chlorine into the system, monitor the reaction by TLC after 3-3.5 hours until the raw materials disappear, and react completely;

[0046]Then dropwise adding 450ml of 450ml mass percentage in the reaction solution is 5% NaOH aqueous solution, separate the water layer after stirring, wash the organic layer with water and merge the water layer; the obtained water phase is heated to reflux, add 3.0g gac to continue Stir for 0.5 hours to decolorize, perform hot filtration at 75°C, and cool the filtrate to room temperature, add 20% NaOH aqueous solution to it to adjust the pH value to 5, filter, and wash the filter cake with water to obtain the product 2-chloro Niacin 13.5g, the yield is 84.7%, and the purity is 99.2%.

[0047] After testing, the melting range of the product is: 181-182°C; ...

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 preparing 2-chloronicotinic acid by using 2,3-pyridinedicarboxylic acid as a raw material. The preparation method comprises the following steps: in the presence of a solvent, 2,3-pyridinedicarboxylic acid and an oxidant , chlorination reagent contact reaction, obtain 2 chloronicotinic acid. The method for preparing 2-chloronicotinic acid of the present invention has the advantages of short route, easy operation, safety and environmental protection, and convenient large-scale production.

Description

technical field [0001] The invention belongs to the production field of pesticides and pharmaceutical products. Specifically, the invention discloses a method for preparing 2-chloronicotinic acid by using 2,3-pyridinedicarboxylic acid as a raw material. Background technique [0002] 2-Chloronicotinic acid is a key intermediate for the preparation of high-efficiency herbicides nicosulfuron, difluzachlor, and important drugs such as nevirapine and mirtazapine, and has important economic and social values. At present, the preparation methods of 2-chloronicotinic acid mainly contain the following types: [0003] 1. Nicotinic acid chloride method [0004] [0005] This method is simple in process, but has the disadvantages of high raw material price and poor product quality, and is difficult to meet the demand of pharmaceutical grade 2-chloronicotinic acid (Said A, Brig W. Pure whit e 2-chloronicotinic acid[P]. DE 2713 316, 1977-10-06). [0006] Two, 3-cyanopyridine chlorin...

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 Patents(China)
IPC IPC(8): C07D213/80C07D213/803
Inventor 潘庆华钱广朱杰朱红薇
Owner JIANGSU HANKUO BIOLOGICAL
Features
  • R&D
  • 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