Preparation method of 2-hydroxyisophthalic acid

A technology of hydroxyisophthalic acid and methoxyisophthalic acid, which is applied in the field of preparation of 2-hydroxyisophthalic acid, can solve problems such as increased reaction energy consumption, high requirements for reactors, and large risk factor, and achieves The effect of short reaction time, low equipment requirements and convenient operation

Inactive Publication Date: 2013-06-19
GUANGXI NORMAL UNIV
View PDF2 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The reaction conditions of this method are harsh, and it is necessary to provide a high temperature of 240oC to keep potassium hydroxide in a molten state, which not only increases the energy consumption of the reaction, but also has high requirements for the reactor and a high risk factor.

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 2-hydroxyisophthalic acid
  • Preparation method of 2-hydroxyisophthalic acid

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0023] A kind of preparation method of 2-hydroxyisophthalic acid, adopts following synthetic route to make:

[0024]

[0025] The specific steps are:

[0026] (1) Add 3.3 g (0.06 mol) of potassium hydroxide, 98 ml (5.4 mol) of water and 19.15 g (0.121 mol) of potassium permanganate to the reactor in sequence, stir and dissolve to obtain an alkaline aqueous solution of potassium permanganate. And slowly add 2.6 ml (0.018 mol) of 2,6-dimethylanisole dropwise to the alkaline aqueous solution of potassium permanganate under stirring to make it fully dispersed.

[0027] (2) Heat up the temperature to 80 oC and reflux under stirring, and the reaction time is 4 h; after the reaction is completed, cool the reaction solution to room temperature, filter it with suction, and then add concentrated hydrochloric acid to the filtrate under stirring to acidify the system until the pH of the system is 3- 4. A large amount of white solid was precipitated, which is the intermediate 2-methoxy...

Embodiment 2

[0034] Carry out according to the method step of embodiment 1, its synthetic route is:

[0035]

[0036] The specific steps are:

[0037] (1) Add 3.3 g (0.06 mol) of potassium hydroxide, 83 ml (4.5 mol) of water and 20.0 g (0.126 mol) of potassium permanganate to the reactor in sequence, stir and dissolve to obtain an alkaline aqueous solution of potassium permanganate. And slowly add 2.6 ml (0.018 mol) of 2,6-dimethylanisole dropwise to the alkaline aqueous solution of potassium permanganate under stirring to make it fully dispersed.

[0038] (2) Heat up the temperature to 80 oC and reflux under stirring, and the reaction time is 4 h; after the reaction is completed, cool the reaction solution to room temperature, filter it with suction, and then add concentrated hydrochloric acid to the filtrate under stirring to acidify the system until the pH of the system is 3- 4. A large amount of white solid was precipitated, which is the intermediate 2-methoxyisophthalic acid, filt...

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

PropertyMeasurementUnit
melting pointaaaaaaaaaa
Login to view more

Abstract

The invention discloses a synthesis method of a drug intermediate 2-hydroxyisophthalic acid, which comprises the following steps: sufficiently dispersing 2,6-dimethylanisole used as a raw material in an alkaline potassium permanganate solution, reacting under reflux for 4 hours, carrying out vacuum filtration to remove insoluble residues, and acidifying the filtrate with hydrochloric acid to obtain an intermediate 2-methoxyisophthalic acid; and dissolving the 2-methoxyisophthalic acid in an HBr-HOAc solution, refluxing while stirring until no gas is emitted, cooling, precipitating a crude product, and recrystallizing to obtain the 2-hydroxyisophthalic acid pure product. The method has the advantages of cheap and accessible raw material, mild and controllable reaction conditions, simple equipment, fewer side reactions, high yield and lower cost, and is convenient to operate and suitable for popularization.

Description

technical field [0001] The invention relates to chemical industry, in particular to a preparation method of 2-hydroxyisophthalic acid. Background technique [0002] 2-Hydroxyisophthalic acid is widely used and is an important intermediate in the synthesis of medicine, pesticide and dye. The current method for preparing 2-hydroxyisophthalic acid is mainly described in "Encyclopedia of Reagents for Organic Synthesis" (Encyclopedia of Organic Synthesis Reagents, edited by Kathlyn A. Parker and Dai-Shi Su, 2001, John Wiley & Sons, Ltd) The method described is as follows: [0003] [0004] It uses PbO 2 As an oxidizing agent, o-methyl salicylic acid is oxidized in a high-temperature potassium hydroxide melt, followed by acidification to prepare 2-hydroxyisophthalic acid. The reaction conditions of this method are harsh, and a high temperature of 240oC needs to be provided to keep the potassium hydroxide in a molten state, which not only increases the energy consumption of ...

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): C07C65/05C07C51/347
Inventor 王凯梁福沛陈自卢邹华红
Owner GUANGXI NORMAL UNIV
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