Preparation method of environment-friendly 4-amino-2, 6-dimethoxy pyrimidine

An environmentally friendly technology of dimethoxypyrimidine, which is applied in organic chemistry and other fields, can solve the problems of long reaction steps, safety risks, and high costs, and achieve the effects of fewer reaction steps, high safety, and less environmental pollution

Active Publication Date: 2022-02-08
ZHEJIANG UNIVERSITY OF SCIENCE AND TECHNOLOGY
View PDF10 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0015] However, the price of the raw material 4,6-dichloropyrimidine-5-carboxylic acid in this method is relatively high, and the reaction steps of this method are long, the cost is high, chlorine gas is also needed, and there are certain safety risks
[0016] It can be seen that the prior art has carried out many researches and improvements on the method of synthesizing 4-amino-2,6-dimethoxypyrimidine, but there are still problems in seeking to improve the safety and environmental protection, simplify the process, reduce costs, and improve the yield. Needs and room for improvement

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
  • Preparation method of environment-friendly 4-amino-2, 6-dimethoxy pyrimidine
  • Preparation method of environment-friendly 4-amino-2, 6-dimethoxy pyrimidine
  • Preparation method of environment-friendly 4-amino-2, 6-dimethoxy pyrimidine

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0043] A method for preparing environmentally friendly 4-amino-2,6-dimethoxypyrimidine, comprising the steps of:

[0044] (1) Add 49 g of 2-methoxyformamidine and 66 g of methyl cyanoacetate into a 500 mL four-necked reaction flask, stir evenly, heat to 80° C., and perform cyclization reaction for 6 h. After the reaction was completed, it was cooled to room temperature, a solid was precipitated, and filtered to obtain 80.8 g of 4-amino-2-methoxy-6-hydroxypyrimidine with a yield of 86%.

[0045] (2) Add 80.8 g of 4-amino-2-methoxy-6-hydroxypyrimidine obtained in step (1) into a 1L three-necked flask containing 323.2 g of phosphorus oxychloride, heat to 90°C, and chlorinate After 4 hours, after recovering excess phosphorus oxychloride under reduced pressure, the remaining product was slowly added to ice water, adjusted to pH 8 with sodium bicarbonate solution with a pH value of 4, and the precipitated solid was filtered and dried to obtain 4- Amino-2-methoxy-6-chloropyrimidine ...

Embodiment 2

[0049] A method for preparing environmentally friendly 4-amino-2,6-dimethoxypyrimidine, comprising the steps of:

[0050] (1) Add 49 g of 2-methoxyformamidine and 66 g of methyl cyanoacetate into a 500 mL four-necked reaction flask, stir evenly, heat to 80° C., and perform cyclization reaction for 6 h. After the reaction was completed, it was cooled to room temperature, and a solid was precipitated. After filtration, 78.9 g of 4-amino-2-methoxy-6-hydroxypyrimidine was obtained, with a yield of 84%.

[0051] (2) Add 78.9 g of 4-amino-2-methoxy-6-hydroxypyrimidine obtained in step (1) into a 1L three-necked flask containing 315.8 g of phosphorus oxychloride, heat to 90°C, and chlorinate After 4 hours, after the excess phosphorus oxychloride was recovered under reduced pressure, the remaining product was slowly added to ice water, adjusted to a pH of 8 with a sodium bicarbonate solution with a pH value of 5, and the precipitated solid was filtered and dried to obtain 4- Amino-2-...

Embodiment 3

[0055] A method for preparing environmentally friendly 4-amino-2,6-dimethoxypyrimidine, comprising the steps of:

[0056] (1) Add 49 g of 2-methoxyformamidine and 66 g of methyl cyanoacetate into a 500 mL four-necked reaction flask, stir evenly, heat to 60° C., and carry out cyclization reaction for 6 h. After the reaction was completed, it was cooled to room temperature, and a solid was precipitated. After filtration, 4-amino-2-methoxy-6-hydroxypyrimidine was obtained with a yield of 63%.

[0057] (2) Add 59.2 g of 4-amino-2-methoxy-6-hydroxypyrimidine obtained in step (1) into a 1 L three-necked flask containing 265 g of phosphorus oxychloride, heat to 90° C., and chlorinate for 4 h Finally, after the excess phosphorus oxychloride was recovered under reduced pressure, the remaining product was slowly added to ice water, adjusted to a pH of 10 with a sodium bicarbonate solution with a pH value of 4, and the precipitated solid was filtered and dried to obtain 4-amino -54.7 g ...

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 provides a preparation method of environment-friendly 4-amino-2, 6-dimethoxy pyrimidine, which comprises the following steps of: carrying out a cyclization reaction on 2-methoxy formamidine and methyl cyanoacetate as initial raw materials under a solvent-free condition to obtain 4-amino-2-methoxy-6-hydroxypyrimidine, carrying out a phosphorus oxychloride chlorination reaction to obtain 4-amino-2-methoxy-6-chloropyrimidine, and carrying out a methoxylation reaction to obtain a target product, namely, 4-amino-2, 6-dimethoxy pyrimidine. The reaction steps are few, the technological operation is simpler, the yield is guaranteed, and the method is suitable for industrial production. According to the preparation method disclosed by the invention, there is no need to use a large amount of solvent, reaction is performed under a solvent-free condition, and the method is high in safety and environment-friendly. Tthe usage amount of phosphorus oxychloride is small, and excessive phosphorus oxychloride is recycled, so that the cost of wastewater treatment is reduced, and the environmental pollution is small.

Description

technical field [0001] The invention relates to the technical field of chemical synthesis, in particular to an environmentally friendly preparation method of 4-amino-2,6-dimethoxypyrimidine. Background technique [0002] Sulfadimethoxine (SDM) is the sulfonamide drug with the strongest antibacterial effect in vivo and in vitro, and it plays a bactericidal effect mainly by inhibiting bacterial dihydrofolate synthase. It has dual effects of antibacterial and protozoa, and has significant curative effect on Toxoplasma gondii, Eperythrozoon, leukocytosis, coccidiosis, Gram-positive bacteria and negative bacteria, etc., and has a good market prospect. And 4-amino-2,6-dimethoxypyrimidine is the key intermediate of sulfadimethoxine (SDM), 4-amino-2,6-dimethoxypyrimidine, CAS number: 3289-50 -7, the chemical formula is C 6 h 9 o 2 N 3 , molecular weight 155.15, light yellow powder, its structure is as follows: [0003] [0004] The barbituric acid method is a relatively ear...

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): C07D239/52
CPCC07D239/52
Inventor 赵先亮徐帆于亚洲孙溢成
Owner ZHEJIANG UNIVERSITY OF SCIENCE AND 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

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