Synthesis process of nicosulfuron original medicine

The technology of nicosulfuron-methyl technical and rimsulfuron-methyl technical application is applied in the field of pesticide synthesis, which can solve the problems of high equipment requirements, environmental pollution, excessive phosgene, etc., and achieves improved synthesis quality and yield, and good atom economy. , the effect of simple operation

Inactive Publication Date: 2017-05-31
江苏长青生物科技有限公司
View PDF2 Cites 11 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

There are many synthetic methods reported in the literature at present, one of which is to make carbamate from sulfonamide, and then condense with aminomeridine. Acid esters and a large amount of expensive organic base catalyst DBU, and a large amount of by-product alcohol or phenol are generated, and the atom economy is poor
Another method is to first make sulfonamide into isocyanate and then add it to aminopyridine. Although the modified method has good atom economy and high yield, the chemical property of the intermediate product isocyanate is lively and easy to deteriorate, and excessive phosgene must be used , has high requirements on equipment and has certain pollution to the environment

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
  • Synthesis process of nicosulfuron original medicine
  • Synthesis process of nicosulfuron original medicine

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0020] 1) In a 250ml flask, add 31.5g (0.2mol) of 2-chloronicotinic acid, then add 81.5g (1.46mol) of thionyl chloride, heat to reflux, keep the reaction for 4 hours, the HPLC detection content is 98.9%, and cool down , and the excess thionyl chloride was distilled off under reduced pressure.

[0021] 2) Add about 100ml of dichloromethane, completely dissolve the solid, cool to 10°C, then add 79g (0.513mol) of 33% dimethylamine aqueous solution dropwise at a constant temperature for 2 hours, stir for 4 hours, and the HPLC detection content is 92 %.

[0022] 3) Stop the reaction, add concentrated hydrochloric acid, adjust the pH to about 3, let stand to separate the liquid, filter, and concentrate the filtrate under reduced pressure to obtain a solid.

[0023] 4) Add about 115ml of 48g (0.1mol) Na 2 S.9H 2 O and 25.6g (0.2mol) of elemental sulfur in aqueous solution were heated to reflux for 20 hours.

[0024] 5) Stop heating, cool to room temperature, add concentrated hydr...

Embodiment 2

[0030] 1) Add 0.22mol of 2-chloronicotinic acid, then add 1.3mol of thionyl chloride, heat to reflux, keep warm for 4 hours, the HPLC detection content is 99.2%, lower the temperature, and remove excess thionyl chloride by vacuum distillation;

[0031] 2) Add 100ml of dichloromethane, dissolve the solid completely, cool to 8°C, then add 0.52mol of 33% dimethylamine aqueous solution dropwise at a constant temperature for 2.2 hours, stir for 3.5 hours, and the HPLC detection content is 92.4%;

[0032] 3) Stop the reaction, add concentrated hydrochloric acid, adjust the pH to 3, let stand to separate the liquid, filter, and concentrate the filtrate under reduced pressure to obtain a solid;

[0033] 4) Add 110ml of 0.09mol Na 2 S.9H 2 O and 0.2mol elemental sulfur aqueous solution, heated to reflux for 22 hours;

[0034] 5) Stop heating, cool to room temperature, add concentrated hydrochloric acid dropwise, adjust the pH value to 2.8, raise the temperature to 75°C, stir for 35 m...

Embodiment 3

[0040] 1) Add 0.22mol of 2-chloronicotinic acid, then add 1.5mol of thionyl chloride, heat to reflux, keep warm for 3.8 hours, the HPLC detection content is 99%, lower the temperature, and remove excess thionyl chloride by vacuum distillation;

[0041] 2) Add 100ml of dichloromethane, dissolve the solid completely, cool to 9°C, then add 0.498mol of 33% dimethylamine aqueous solution dropwise at a constant temperature for 2.3 hours, stir for 5 hours, and the HPLC detection content is 92.6%;

[0042] 3) Stop the reaction, add concentrated hydrochloric acid, adjust the pH to 3.2, let stand to separate the liquid, filter, and concentrate the filtrate under reduced pressure to obtain a solid;

[0043] 4) Add 125ml of 0.12mol Na 2 S.9H 2 O and 0.24mol elemental sulfur aqueous solution were heated to reflux for 20 hours;

[0044] 5) Stop heating, cool to room temperature, add concentrated hydrochloric acid dropwise, adjust the pH value to 3.2, raise the temperature to 75°C, stir fo...

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 synthesis process of a nicosulfuron original medicine. In the method, 2-chloronicotinic acid is used as a raw material to synthesize an intermediate 2-sulfunylchloro-N,N-dimethyl nicotinamide, which is then reacted with amino pyrimidine to produce the nicosulfuron. The method has good atom economy and meanwhile avoids use of highly-toxic raw materials, such as phosgene, and expensive catalysts. The method has simple operations, is low in pollution and is low in cost; by means of continuous material feeding and continuous distillation, continuous synthesis of the nicosulfuron original medicine is achieved, and synthesis quality and yield of the nicosulfuron are greatly improved.

Description

technical field [0001] The invention relates to a synthesis process of nicosulfuron original drug, belonging to the technical field of pesticide synthesis. Background technique [0002] Nicosulfuron is a new generation of broad-spectrum, high-efficiency, low-toxicity, low-residue sulfonylurea herbicide, and it is one of the best herbicide varieties for corn fields so far. There are many synthetic methods reported in the literature at present, one of which is to make carbamate from sulfonamide, and then condense with aminomeridine. Ester and a large amount of expensive organic base catalyst DBU, and a large amount of by-product alcohol or phenol are generated, and the atom economy is poor. Another method is to first make sulfonamide into isocyanate and then add it to aminopyridine. Although the modified method has good atom economy and high yield, the chemical property of the intermediate product isocyanate is lively and easy to deteriorate, and excessive phosgene must be us...

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): C07D401/12
CPCC07D401/12
Inventor 于国权孙霞林丁华平周鹏袁宇吕佳杭
Owner 江苏长青生物科技有限公司
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