A kind of synthetic method of 2-chloropyridine

A synthetic method, the technology of chloropyridine, applied in the direction of organic chemistry, etc., can solve the problems of reducing production costs, and achieve the effects of low cost, safe operation and mild reaction

Active Publication Date: 2018-02-23
ANHUI UNIVERSITY OF TECHNOLOGY
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The object of the present invention is to provide a kind of synthetic method of 2-chloropyridine, replace Cl with cheap hydrochloric acid and hypochlorite by-product in industrial production 2 , COCl 2 etc. as chlorinating agents to solve environmental and safety issues in the production of 2-chloropyridine and reduce production costs

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 synthetic method of 2-chloropyridine
  • A kind of synthetic method of 2-chloropyridine
  • A kind of synthetic method of 2-chloropyridine

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0018] Add 120ml of sodium hypochlorite solution (13% available chlorine) into a 500mL flask, add 15g of pyridine under constant stirring, and mix well. 70ml of 20% hydrochloric acid was slowly added dropwise through the dropping funnel, and stirred at room temperature for 1h. Then, it was heated to 60°C and the reaction was continued for 2h. After the reaction is completed, a certain amount of NaOH solution is added to neutralize the pH to 9-11, and the reactant is extracted three times with 500 ml of chloroform. The obtained extract phase was distilled to remove the solvent chloroform sequentially, and unreacted pyridine (10.1 g) was recovered to finally obtain 6.9 g of chloropyridine product, and the mass yield of chloropyridine was 141%. The chloropyridine product is analyzed by GC-MS, mainly including 2-chloropyridine and a small amount of other dichloropyridines such as 2,6-dichloropyridine, 3-chloropyridine, 4-chloropyridine and 2,5-dichloropyridine . Among them, the...

Embodiment 2

[0020] Add 180ml of sodium hypochlorite solution (8% available chlorine) in a 500mL flask, add 15g of pyridine under constant stirring, and mix well. 80ml of 20% hydrochloric acid was slowly added dropwise through the dropping funnel, and stirred at room temperature for 2h. Then, it was heated to 80°C and the reaction was continued for 2h. After the reaction is completed, a certain amount of NaOH solution is added to neutralize the pH to 9-11, and the reactant is extracted three times with 500 ml of chloroform. The obtained extract phase was distilled to remove the solvent chloroform sequentially, and unreacted pyridine (10.3 g) was recovered to finally obtain 6.5 g of chloropyridine product, and the mass yield of chloropyridine was 138%. The chloropyridine product is analyzed by GC-MS, mainly including 2-chloropyridine and a small amount of other dichloropyridines such as 2,6-dichloropyridine, 3-chloropyridine, 4-chloropyridine and 2,5-dichloropyridine . Among them, the se...

Embodiment 3

[0022] Add 120ml of sodium hypochlorite solution (13% available chlorine) into a 500mL flask, add 15g of pyridine under constant stirring, and mix well. 60ml of 25% hydrochloric acid was slowly added dropwise through the dropping funnel, and stirred at room temperature for 1h. Then, it was heated to 60° C. and the reaction was continued for 1 h. After the reaction is completed, a certain amount of NaOH solution is added to neutralize the pH to 9-11, and the reactant is extracted three times with 500 ml of chloroform. The obtained extract phase was distilled to remove the solvent chloroform sequentially, and unreacted pyridine (10.8 g) was recovered to finally obtain 5.8 g of chloropyridine product, and the mass yield of chloropyridine was 138%. The chloropyridine product is analyzed by GC-MS, mainly including 2-chloropyridine and a small amount of other dichloropyridines such as 2,6-dichloropyridine, 3-chloropyridine, 4-chloropyridine and 2,5-dichloropyridine . Among them, ...

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 2-chloropyridine synthetic method, which belongs to the technical field of fine chemical engineering. The method comprises the following steps: adding pyridine into a hypochloric acid salt solution, uniformly mixing the solution, slowly adding hydrochloric acid drop by drop at room temperature, stirring a mixture and reacting the mixture for 1-2 hours; then heating the material to the temperature of 60-80 DEG C, continuously reacting the material for 1-2 hours; and finally, adding a certain amount of a NaOH solution and neutralizing the solution to a pH value of 9-11, extracting a reactant by using trichloromethane and separating the reactant; distilling an extract phase and removing a trichloromethane solvent in order, recovering the unreacted pyridine to obtain the chloropyridine product. According to the invention, a GC / MS analysis on the chloropyridine product is carried out, selectivity of 2-chloropyridine can reach 83%. The hydrochloric acid and hypochlorite by-product with low cost in industrial production can substitute a chlorinating agent such as Cl2, reaction condition is mild, selectivity is good, process is simple, cost is low, and environment and safety problems during the production process of 2-chloropyridine can be solved.

Description

technical field [0001] The invention belongs to the technical field of fine chemicals, and in particular relates to the synthesis technology of 2-chloropyridine intermediates such as medicines and pesticides. Background technique [0002] 2-Chloropyridine is an important organic synthesis intermediate and fine chemical raw material. It is mainly used in the synthesis of "three medicines" such as fungicides, insecticides, and herbicides, and daily chemical additives. Its downstream products have high efficiency, low It is an important organic synthesis intermediate. [0003] At present, the synthesis of 2-chloropyridine mainly includes functional group conversion method and direct substitution chlorination method. The former uses pyridine derivatives such as 2-aminopyridine and 2-hydroxypyridine as raw materials, and the source of raw materials is difficult and the cost is high. The direct substitution chlorination of pyridine and its derivatives is mainly based on Cl 2 As...

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): C07D213/61
CPCC07D213/61
Inventor 王知彩刘善和杨红兵水恒福雷智平任世彪潘春秀吴德清
Owner ANHUI UNIVERSITY OF TECHNOLOGY
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