Supercharge Your Innovation With Domain-Expert AI Agents!

Preparation method of high-purity methyl 4-chloroacetoacetate

A technology of methyl acetate and chloroacetyl, which is applied in the field of preparation of high-purity methyl 4-chloroacetoacetate, can solve the problems of low chlorination reaction efficiency and failure to meet the use requirements, and achieve good and practical chlorination reaction effects The effect of high efficiency and high efficiency chlorination reaction

Active Publication Date: 2020-12-04
JIANGSU HENGAN CHEM
View PDF1 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The synthesis method of methyl 4-chloroacetoacetate is comparatively consistent now, and wherein when carrying out chlorination reaction, the reaction equipment that adopts now, chlorination reaction efficiency is not high, can not satisfy present use requirement

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 high-purity methyl 4-chloroacetoacetate
  • Preparation method of high-purity methyl 4-chloroacetoacetate

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0028] A preparation method of high-purity methyl 4-chloroacetoacetate, comprising the steps of:

[0029] Step 1: Add dichloromethane solvent and diketene into the reaction kettle, and stir the reaction at a temperature of -5°C;

[0030] Step 2: Add sodium hydroxide to the reactor, and maintain the temperature in the reactor at -25°C;

[0031] Step 3: feed chlorine gas into the solution in the reactor to carry out chlorination reaction;

[0032] Step 4: Add methanol dropwise to the solution in the reactor, and stir evenly;

[0033] Step 5: the gas in the reaction kettle is discharged to obtain the crude product of methyl 4-chloroacetoacetate;

[0034] Step 6: purifying the obtained crude methyl 4-chloroacetoacetate.

Embodiment 2

[0036] A preparation method of high-purity methyl 4-chloroacetoacetate, comprising the steps of:

[0037] Step 1: Add dichloromethane solvent and diketene into the reaction kettle, and stir the reaction at the temperature of -15°C;

[0038] Step 2: Add sodium hydroxide to the reactor, and maintain the temperature in the reactor at -30°C;

[0039] Step 3: feed chlorine gas into the solution in the reactor to carry out chlorination reaction;

[0040] Step 4: Add methanol dropwise to the solution in the reactor, and stir evenly;

[0041] Step 5: the gas in the reaction kettle is discharged to obtain the crude product of methyl 4-chloroacetoacetate;

[0042] Step 6: purifying the obtained crude methyl 4-chloroacetoacetate.

Embodiment 3

[0044] A preparation method of high-purity methyl 4-chloroacetoacetate, comprising the steps of:

[0045] Step 1: Add dichloromethane solvent and diketene into the reaction kettle, and stir the reaction at a temperature of -10°C;

[0046] Step 2: Add sodium hydroxide to the reactor, and maintain the temperature in the reactor at -27.5°C;

[0047] Step 3: feed chlorine gas into the solution in the reactor to carry out chlorination reaction;

[0048] Step 4: Add methanol dropwise to the solution in the reactor, and stir evenly;

[0049] Step 5: the gas in the reaction kettle is discharged to obtain the crude product of methyl 4-chloroacetoacetate;

[0050] Step 6: purifying the obtained crude methyl 4-chloroacetoacetate.

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 preparation method of high-purity methyl 4-chloroacetoacetate, wherein the preparation method comprises the following steps: step 1, adding a dichloromethane solvent and ketene dimer into a reaction kettle, and carrying out stirring reaction at the temperature of -15 to -5 DEG C; step 2, adding sodium hydroxide into the reaction kettle, and maintaining the temperature inthe reaction kettle at the temperature of -30 to -25 DEG C; step 3, introducing chlorine into the solution in the reaction kettle, and carrying out a chlorination reaction; step 4, dropwise adding methanol into the solution in the reaction kettle, and uniformly stirring; step 5, discharging gas in the reaction kettle to obtain a crude product of methyl 4-chloroacetoacetate; and step 6, purifying the obtained crude product of methyl 4-chloroacetoacetate. The method disclosed by the invention is simple and clear and is convenient to implement, the reaction kettle adopted by the method is diversein function, the efficient chlorination reaction can be realized, the practical efficiency of chlorine is high, the chlorination reaction effect is good, and the current use requirements are met.

Description

technical field [0001] The invention relates to the field of chemical preparation, in particular to a method for preparing high-purity methyl 4-chloroacetoacetate. Background technique [0002] Methyl 4-chloroacetoacetate is a colorless light yellow liquid, which is a good intermediate for pharmaceutical synthesis and is mainly used to produce oxiracetam, which is a drug for treating cerebrovascular diseases. [0003] At present, the main conventional production method of methyl 4-chloroacetoacetate in industrial production is: batch production, first dissolving diketene in a solvent, and cooling it to -30°C ~ -10°C, starting stirring, and pouring it into the reaction kettle Introduce a certain amount of chlorine gas at a certain flow rate, keep it warm at -30°C to -10°C for 1 to 2 hours, drop a certain amount of methanol into it after the chlorination reaction is completed, control the reaction temperature at 0 to 5°C, and raise the temperature to 20-25°C, keep warm for 1 ...

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
IPC IPC(8): C07C67/46C07C69/716B01J4/00B01J19/00B01J19/18
CPCC07C67/46B01J19/18B01J19/0066B01J19/0073B01J19/0053B01J19/0013B01J4/001B01J2204/002B01J2219/00087B01J2219/00155C07C69/716
Inventor 陈敏方
Owner JIANGSU HENGAN CHEM
Features
  • R&D
  • Intellectual Property
  • Life Sciences
  • Materials
  • Tech Scout
Why Patsnap Eureka
  • Unparalleled Data Quality
  • Higher Quality Content
  • 60% Fewer Hallucinations
Social media
Patsnap Eureka Blog
Learn More

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2025 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com