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

Method for synthesizing guaiacol

A technology of guaiacol and catechol, applied in organic chemistry, ether preparation and other directions, to achieve the effects of high yield, short process flow and mild reaction conditions

Inactive Publication Date: 2010-01-06
BEIJING UNIV OF CHEM TECH
View PDF0 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Wherein, synthetic method (5) becomes the development direction of industrialized synthesis of guaiacol because of simple process and low cost, but there are parallel side reactions in the reaction process simultaneously, generating various by-products (such as o-dimethoxybenzene, toluene Catechol, Methylguaiacol, etc.)

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
  • Method for synthesizing guaiacol
  • Method for synthesizing guaiacol

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0020] 1) After adding 0.2mol catechol, polyethylene glycol-400, 0.18mol sodium hydroxide, 20ml water and 60ml toluene, which account for 1% of the catechol mass, into the reactor, fill it with 0.20mol methyl chloride gas, Stir, the temperature rises to 100°C within 30 minutes and react for 1 hour;

[0021] 2) Add 1:1 hydrochloric acid to the reaction solution in step 1) to adjust the pH=5 to 6, let stand for stratification, weigh the toluene phase, and obtain the yield of guaiacol by gas chromatography analysis is 70.00%, selectivity It was 87.64%, and the conversion rate of catechol was 79.83%.

Embodiment 2

[0023] 1) After adding 0.2mol catechol, polyethylene glycol-6000, 0.22mol sodium hydroxide, 20ml water and 60ml toluene, which account for 4% of catechol mass, into the reactor, fill it with 0.28mol methyl chloride gas, Stirring, the temperature rose to 140°C within 30 minutes and reacted for 4 hours;

[0024] 2) Add 1:1 hydrochloric acid to the reaction solution in step 1) to adjust the pH=5 to 6, let stand for stratification, weigh the toluene phase, and obtain the yield of guaiacol by gas chromatography analysis is 87.24%, selectivity It is 87.24%, and the conversion rate of catechol is 100%.

Embodiment 3

[0026] 1) After adding 0.2mol catechol, polyethylene glycol-6000, 0.22mol sodium hydroxide, 20ml water and 60ml toluene, which account for 5% of catechol mass, into the reactor, fill it with 0.28mol methyl chloride gas, Stirring, the temperature rose to 140°C within 30 minutes and reacted for 4 hours;

[0027] 2) Add 1:1 hydrochloric acid to the reaction solution in step 1) to adjust the pH=5 to 6, let stand for stratification, weigh the toluene phase, and obtain the yield of guaiacol by gas chromatography analysis is 79.81%, selectivity is 85.52%, and the conversion rate of catechol is 93.32%.

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 synthesizing guaiacol, and belongs to the technical field of organic chemical synthesis. The prior method for synthesizing the guaiacol has more side reactions. The method comprises the following steps: adding pyrocatechol, polyethylene glycol with the molecular weight of 400 to 14,000, sodium hydroxide, methyl chloride, methylbenzene solvent and water into an autoclave, and heating, stirring and refluxing the mixture for 1 to 10 hours at the temperature of between 100 and 150 DEG C; and adding hydrochloric acid into the mixture after reacting to control the pH at 5 to 6, standing and demixing the mixture to obtain a methylbenzene layer containing the guaiacol on the upper layer, and evaporating methylbenzene to obtain the guaiacol, wherein the molar ratio of the pyrocatechol to the methyl chloride to the sodium hydroxide is 1:1:0.9-1:1.8:1.2, and the adding amount of the polyethylene glycol is 1 to 10 percent of the mass of the pyrocatechol. The method has the advantages of high yield, low cost, and the like.

Description

technical field [0001] The invention belongs to the technical field of organic chemical synthesis, and in particular relates to a method for synthesizing guaiacol by using polyethylene glycol as a phase transfer catalyst. Background technique [0002] Guaiacol, also known as o-methoxyphenol or o-hydroxyanisole, is an important fine chemical intermediate widely used in the synthesis of medicine, spices and dyes, especially in the synthesis of vanillin ). At present, there are the following five synthetic methods of guaiacol: (1) it is obtained by diazotization and hydrolysis of o-aminoanisole; (2) it is obtained by catechol and methyl iodide under the action of NaOH; (3) taking o-chlorophenol as a raw material to synthesize guaiacol under the action of a catalyst; (4) carrying out hydroxyl oxygen monoetherification reaction with catechol, dimethyl sulfate and dimethyl carbonate to obtain guaiacol; (5) Methanol and catechol are reacted in gas phase under normal pressure, and...

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): C07C43/23C07C41/01
Inventor 张敬畅张小亮张彦曹维良
Owner BEIJING UNIV OF CHEM TECH
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