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

A kind of purification method of 5-methylpyrazine-2-carboxylic acid crude product

A technology of methylpyrazine and purification method, applied in chemical instruments and methods, separation methods, organic chemistry and other directions, can solve the problems of high production cost, large amount of mother liquor, and reduced purity, and achieves mass production and uniform material. , the effect of uncomplicated steps

Active Publication Date: 2021-06-22
江苏惠利生物科技有限公司
View PDF3 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the crystallization process takes a long time, the yield is low, the amount of mother liquor is large, and organic impurities will also attach to the crystals in a small amount, resulting in a decrease in purity, and the production cost is also high, which has serious shortcomings.

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 purification method of 5-methylpyrazine-2-carboxylic acid crude product
  • A kind of purification method of 5-methylpyrazine-2-carboxylic acid crude product
  • A kind of purification method of 5-methylpyrazine-2-carboxylic acid crude product

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0031] (1) Adjust the pH of the 5-methylpyrazine-2-carboxylic acid solution to 2.0, and the 5-methylpyrazine-2-carboxylic acid solid is precipitated, centrifuged to obtain 5-methylpyrazine-2-carboxylic acid Crude;

[0032] (2) Spread the crude 5-methylpyrazine-2-carboxylic acid in the trough of the purification device, and stir at a stirring speed of 10r / min;

[0033] (3) Raise the temperature of the trough to 60°C to further remove moisture until the moisture content drops to 0.5%;

[0034] (4) Raise the temperature of the trough to 80°C, and start the vacuum pump and cooling system at the same time to vacuumize, and the vacuum degree is controlled at 500Pa;

[0035] (5) Nitrogen gas is introduced into the trough, and the vacuum degree is controlled at 2000Pa;

[0036] (6) The high-purity 5-methylpyrazine-2-carboxylic acid gas will be pumped into the crystallization kettle along with the nitrogen and vacuum system and condensed on the wall of the kettle, and the temperature...

Embodiment 2

[0044] (1) Adjust the pH of the 5-methylpyrazine-2-carboxylic acid solution to 1.8, the 5-methylpyrazine-2-carboxylic acid solid precipitates, and centrifuges to obtain 5-methylpyrazine-2-carboxylic acid Crude;

[0045] (2) Spread the crude product of 5-methylpyrazine-2-carboxylic acid in the trough of the purification device (the same as that used in Example 1) and stir at a stirring speed of 10r / min;

[0046] (3) Raise the temperature of the trough to 60°C to further remove moisture until the moisture content drops to 0.2%;

[0047] (4) Raise the temperature of the trough to 100°C, and start the vacuum pump and cooling system at the same time to vacuumize, and the vacuum degree is controlled at 650Pa;

[0048] (5) Nitrogen gas is introduced into the trough, and the vacuum degree is controlled at 1500Pa;

[0049] (6) The high-purity 5-methylpyrazine-2-carboxylic acid gas will be pumped into the crystallization kettle along with the nitrogen and vacuum system and condensed on ...

Embodiment 3

[0052] (1) Adjust the pH of the 5-methylpyrazine-2-carboxylic acid solution to 1.8, the 5-methylpyrazine-2-carboxylic acid solid precipitates, and centrifuges to obtain 5-methylpyrazine-2-carboxylic acid Crude;

[0053] (2) Spread the crude product of 5-methylpyrazine-2-carboxylic acid in the trough of a purification device (the same as that used in Example 1) and stir at a stirring speed of 50 r / min;

[0054] (3) Raise the temperature of the trough to 60°C to further remove moisture until the moisture content drops to 0.1%;

[0055] (4) Raise the temperature of the trough to 100°C, and start the vacuum pump and cooling system at the same time to vacuumize, and the vacuum degree is controlled at 500Pa;

[0056] (5) Nitrogen gas is introduced into the trough, and the vacuum degree is controlled at 5000Pa;

[0057] (6) The high-purity 5-methylpyrazine-2-carboxylic acid gas will be pumped into the crystallization kettle along with the nitrogen and vacuum system and condensed on...

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 purifying crude 5-methylpyrazine-2-carboxylic acid. The method utilizes a vacuum sublimation and desublimation process to prepare high-purity 5-methylpyrazine-2-carboxylic acid. The preparation process is followed by dehydration of the crude product, heating up and vacuuming to open nitrogen for sublimation, cooling and desublimation, opening the tank, and receiving the material. The 5-methylpyrazine-2-carboxylic acid white transparent solid with a total yield of more than 80% and a purity of more than 99% can be obtained. The method is simple in process, does not need to use organic solvents, has no waste water, is more environmentally friendly, has low cost, high product purity and high yield, and is suitable for industrial production.

Description

technical field [0001] The invention belongs to the field of purification of pharmaceutical intermediates, in particular to a method for purifying 5-methylpyrazine-2-carboxylic acid by sublimation and desublimation. Background technique [0002] 5-Methylpyrazine-2-carboxylic acid is a key intermediate of the drugs glipizide, lezhiping and the blood lipid-lowering drug acipimox, and it has attracted more and more attention in the market. Especially for the blood lipid-lowering drug acipimox, 5-methylpyrazine-2-carboxylic acid can be prepared by only one-step oxidation reaction, so high-purity 5-methylpyrazine-2-carboxylic acid is required. [0003] At present, the purification method of 5-methylpyrazine-2-carboxylic acid mainly adopts the method of crystallization and recrystallization. However, the crystallization process takes a long time, the yield is low, the amount of mother liquor is large, and organic impurities will attach to the crystals in a small amount, resulting...

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): B01D7/00B01D7/02C07D241/24
Inventor 李赟高郭宏明孙重亮朱宏文张恒家
Owner 江苏惠利生物科技有限公司
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