Synthesis method of 4-chloro-3-methoxy-2-methylpyridine-N-oxide

A technology of methyl pyridine and synthesis method, applied in directions such as organic chemistry, can solve problems such as poor catalytic effect, low yield of pyridine-N-oxide, etc., achieve mild reaction, improve oxidation reaction effect, and reduce the effect of raw material usage

Active Publication Date: 2017-09-05
CHUZHOU UNIV +1
View PDF6 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The catalyst is solid phosphotungstic acid, the catalytic effect is poor, and the yield of pyridine-N-oxide is low

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 method of 4-chloro-3-methoxy-2-methylpyridine-N-oxide
  • Synthesis method of 4-chloro-3-methoxy-2-methylpyridine-N-oxide
  • Synthesis method of 4-chloro-3-methoxy-2-methylpyridine-N-oxide

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0027] A kind of synthetic method of Pandoprazole intermediate 4-chloro-3-methoxyl group-2-picoline-N-oxide compound of the present invention, such as image 3 As shown, follow the steps below:

[0028] Step 1, dissolving 10 parts by weight of phosphotungstic acid in neutral water to obtain a 20% phosphotungstic acid solution;

[0029] Step 2, weigh 250 parts by weight of 4-chloro-3-methoxy-2-picoline, slowly add the phosphotungstic acid solution prepared in step 1 under stirring, stir until completely mixed, and heat in a water bath to raise the temperature To 90°C, 300 parts by weight of hydrogen peroxide with a mass concentration of 35% was added dropwise, and the dropping rate of hydrogen peroxide was 50 parts by weight / hour; and then kept at 83°C for 5 hours to obtain a reaction solution;

[0030] Step 3, after cooling the reaction solution to 25°C, add a dilute alkali solution (aqueous sodium hydroxide solution with a mass concentration of 15%) to adjust the pH to 7-9, ...

Embodiment 2

[0032] A kind of synthetic method of Pandoprazole intermediate 4-chloro-3-methoxyl group-2-picoline-N-oxide of the present invention, specifically carry out according to the following steps:

[0033] Step 1, dissolving 12 parts by weight of phosphotungstic acid in weakly acidic water to obtain a 25% mass concentration of phosphotungstic acid solution;

[0034]Step 2, weigh 220 parts by weight of 4-chloro-3-methoxy-2-methylpyridine, slowly add the phosphotungstic acid solution prepared in step 1 under stirring, stir until completely mixed, and heat up in a water bath To 87°C, 350 parts by weight of hydrogen peroxide with a mass concentration of 35% was added dropwise, and the dropping rate of hydrogen peroxide was 60 parts by weight / hour; and then kept at 85°C for 5 hours to obtain a reaction solution;

[0035] Step 3, after cooling the reaction solution to 30°C, add a dilute alkali solution (aqueous sodium hydroxide solution with a mass concentration of 12%) to adjust the pH t...

Embodiment 3

[0037] A kind of synthetic method of Pandoprazole intermediate 4-chloro-3-methoxyl group-2-picoline-N-oxide of the present invention, specifically carry out according to the following steps:

[0038] Step 1, dissolving 13 parts by weight of phosphotungstic acid with weakly acidic water to obtain a 30% mass concentration of phosphotungstic acid solution;

[0039] Step 2, weigh 200 parts by weight of 4-chloro-3-methoxy-2-picoline, slowly add the phosphotungstic acid solution prepared in step 1 under stirring, stir until completely mixed, and heat the water bath to raise the temperature To 85°C, 380 parts by weight of hydrogen peroxide with a mass concentration of 35% was added dropwise, and the dropping rate of hydrogen peroxide was 65 parts by weight / hour; and then kept at 88°C for 5 hours to obtain a reaction solution;

[0040] Step 3, after cooling the reaction solution to 40°C, add a dilute alkaline solution (8% sodium hydroxide aqueous solution) to adjust the pH to 7-9, the...

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 synthesis method of a pantoprazole intermediate compound 4-chloro-3-methoxy-2-methylpyridine-N-oxide. The synthesis method comprises the following steps: by taking 4-chloro-3-methoxy-2-methylpyridine as a raw material and a phosphotungstic acid solution as a catalyst, performing an oxidation reaction with oxydol; and after the oxidation reaction, regulating the pH value to 7-9 with sodium hydroxide to decompose the excessive oxydol, extracting 4-chloro-3-methoxy-2-methylpyridine-N-oxide with dichloromethane, washing the extract liquid with water to a neutral state, adding anhydrous Na2SO4, drying, and evaporating under reduced pressure to remove the dichloromethane so as to obtain the 4-chloro-3-methoxy-2-methylpyridine-N-oxide. The synthesis method has the advantages of mild reaction conditions, high safety, high yield, high operation convenience, no waste acid discharge, greenness, environment friendliness and low cost, thereby being more suitable for industrial production.

Description

technical field [0001] The invention belongs to the technical field of medicine synthesis, and relates to a synthesis method of a pandoprazole intermediate 4-chloro-3-methoxy-2-methylpyridine-N-oxide. Background technique [0002] Pandoprazole has been widely used in the world in recent years for gastrointestinal diseases caused by Helicobacter pylori, and it is also a kind of proton pump inhibitor drug with better effect. It was developed by German company Byk Gulden; 2-chloromethyl-3,4- Dimethoxypyridine hydrochloride is one of the two intermediates for the synthesis of Pandoprazole, and 4-chloro-3-methoxy-2-methylpyridine-N-oxide is the synthesis of 2-chloromethyl-3, The important intermediate base of 4-dimethoxypyridine hydrochloride; Methylation first, followed by ammoniation and chlorination to obtain 4-chloro-3-methoxy-2-picoline, and then hydrogen peroxide oxidation to obtain 4-chloro-3-methoxy-2-methyl Pyridine-N-oxide, and then through sodium methoxide methoxide,...

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): C07D213/89
CPCC07D213/89
Inventor 夏家信王永贵葛秀涛耿庆保杨志健
Owner CHUZHOU UNIV
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