Preparation method for alpha-acetyl-gamma-butyrolactone

A technology of butyrolactone and acetyl group, applied in the field of preparation of pharmaceutical intermediates, can solve the problems of low safety factor, environmental pollution and high cost, and achieve the effects of saving input cost, reducing production cost and preventing the occurrence of punching

Active Publication Date: 2011-11-02
山西三维华邦集团有限公司 +1
View PDF10 Cites 16 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] In order to solve the problems of low safety factor, low yield, high cost and environmental pollution in the prior art, the invention provides a method for preparing α-acetyl-γ-butyrolactone, which uses cheap methyl acetate Ethyl acetate is used as an acylating agent instead of ethyl acetate; toxic solvents such as benzene are replaced by excess methyl acetate; sodium sand is used as a catalyst instead of block sodium; the mixed product is acidified and extracted after solid-liquid separation instead of a mixed product. to prepare alpha-acetyl-gamma-butyrolactone

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0023] The reactor was first purged with nitrogen, then γ-butyrolactone and metal sodium were added, the temperature was raised to 105°C under a nitrogen atmosphere, stirred at high speed, and rapidly cooled to 60°C after the metal sodium formed sodium sand. Add methyl acetate to the above reaction system, and keep the reaction at the reflux temperature for 8 hours, wherein the molar ratio of γ-butyrolactone, methyl acetate and metal sodium is 1:5:1.2. After the reaction is complete, the mixture is separated by suction filtration, and methyl acetate and by-product methanol in the filtrate are recovered. The solid product sodium salt obtained is the sodium salt of α-acetyl-γ-butyrolactone with dilute H 2 SO 4 Neutralize to a pH value of 3, and then extract with chloroform, wherein the molar ratio of γ-butyrolactone, acid, and extractant is 1:0.8:4. After the extraction phase was distilled to recover chloroform, 21.8 g of the product α-acetyl-γ-butyrolactone was obtained. The...

Embodiment 2

[0025] The reactor was first purged with nitrogen, then γ-butyrolactone and metal sodium were added, the temperature was raised to 115°C under a nitrogen atmosphere, stirred at high speed, and rapidly cooled to 50°C after the metal sodium formed sodium sand. Add methyl acetate to the above reaction system, and keep the reaction at the reflux temperature for 3 hours, wherein the molar ratio of γ-butyrolactone, methyl acetate and metal sodium is 1:6:1. After the reaction is complete, the mixture is separated by suction filtration, and methyl acetate and by-product methanol in the filtrate are recovered. The solid product sodium salt obtained is the sodium salt of α-acetyl-γ-butyrolactone with dilute H 3 PO 4 Neutralize to a pH value of 5, and then extract with carbon tetrachloride, wherein the molar ratio of gamma-butyrolactone, acid, and extractant is 1:1:5. After recovering carbon tetrachloride by distilling the extract phase, 21.3 g of the product α-acetyl-γ-butyrolactone c...

Embodiment 3

[0027] The reactor was first purged with nitrogen, then γ-butyrolactone and metal sodium were added, the temperature was raised to 110°C under nitrogen atmosphere, stirred at high speed, and cooled rapidly to 55°C after the metal sodium formed sodium sand. Add methyl acetate to the above reaction system, and keep the reaction at the reflux temperature for 10 hours, wherein the molar ratio of γ-butyrolactone, methyl acetate and metal sodium is 1:5.5:1.1. After the reaction is complete, the mixture is separated by suction filtration, and methyl acetate and by-product methanol in the filtrate are recovered. The sodium salt of the obtained solid product, that is, the sodium salt of α-acetyl-γ-butyrolactone, is neutralized with dilute acetic acid to a pH value of 4, and then extracted with dichloroethane, wherein γ-butyrolactone, acid, The molar ratio of extractant is 1:1.2:4.5. After dichloroethane was recovered by distillation of the extract phase, 21.5 g of the product α-acetyl...

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

In order to solve the problems of a low safety factor, low yield, high cost, environmental pollution and the like existing in the prior art, the invention provides a preparation method for alpha-acetyl-gamma-butyrolactone. In the method, gamma-butyrolactone and methyl acetate are used as reaction raw materials and metallic sodium is used as a catalyst; the final product is prepared through the phases of reaction, separation, neutralization and extraction. According to the invention, methyl acetate is used as the reaction raw material and a reaction solvent, which on one hand enables production cost to be reduced, the reaction rate to be slowed and dashing out of reacting materials to be avoided, and on the other hand avoids environmental pollution and affection on product quality caused by utilization of benzene solvents; preparation of the catalyst into sodium sand can improve reaction efficiency; high purity alpha-acetyl-gamma-butyrolactone can be obtained through neutralization andextraction of the solid resultants alpha-acetyl-gamma-butyrolactone sodium salt of the reaction which have been subjected to solid-liquid separation without underpressure distillation, thereby effectively improving production efficiency and reducing production cost; the acidic neutral solution used in the invention can be used repeatedly, thereby avoiding environmental pollution by the solution.

Description

technical field [0001] The invention relates to a preparation method of a pharmaceutical intermediate, in particular to a preparation method of α-acetyl-γ-butyrolactone. Background technique [0002] α-acetyl-γ-butyrolactone is an important intermediate for the preparation of vitamin B1 drugs. At present, there are multiple methods for synthesizing α-acetyl-γ-butyrolactone, but the commonly used preparation methods mainly contain two routes, one of which is a process using ethylene oxide and ethyl acetoacetate as starting materials, The second is a process using gamma-butyrolactone and ethyl acetate as starting materials. [0003] In the process of using ethylene oxide and ethyl acetoacetate as starting materials, the preparation method disclosed in Japanese Patent Publication No. 40-23006 is in alcohol solvent, in alkali metal alcoholate, alkali metal or its hydroxide In the presence of alkali components, ethyl acetoacetate and ethylene oxide are reacted, and the reaction...

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): C07D307/33B01J23/04B01J35/08
Inventor 薛永强张建平崔子祥闫济民李文杰
Owner 山西三维华邦集团有限公司
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