Preparation method of methoxybenzoic acid

A methoxybenzyl, acid-base technology, applied in the preparation of carboxylate, carboxylate, carboxynitrile and other directions, can solve the problems of large environmental pollution, large consumption of alkali, complicated operation, etc. The effect of less pollution, less alkali consumption and simple operation

Active Publication Date: 2014-11-19
联化科技(上海)有限公司 +2
View PDF4 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0010] The technical problem to be solved by the present invention is to provide a method for overcoming the disadvantages of using highly toxic or expensive reagents, large alkali consumption, large environmental pollution, complicated operation and low yield in the existing preparation method of methoxybenzoic acid. A method for preparing methoxybenzoic acid, the method is cheap and easy to obtain raw materials, uses cheap and safe reagents, has small alkali consumption, less environmental pollution, adopts a one-pot method, simple operation, high yield, and is suitable for industrial production

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 methoxybenzoic acid
  • Preparation method of methoxybenzoic acid
  • Preparation method of methoxybenzoic acid

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0041] Add 16.2g of 30% sodium methoxide and 0.1mol of o-chlorobenzonitrile into a 100ml autoclave, replace the air with nitrogen three times, seal the reaction kettle, raise the temperature to 100°C-120°C, the reaction pressure is about 0.3Mpa-0.5Mpa, and Insulate for 2 hours to 4 hours, HPLC analysis o-chlorobenzonitrile <0.5% is the end point, cool the reaction solution to less than 50°C, add 14.7g of 30% liquid alkali dropwise, heat up and distill to recover methanol, when the internal temperature reaches 100°C, Change to reflux, and keep the reflux reaction for 2 hours to 8 hours. When o-methoxybenzonitrile <0.5% is the end point, cool the reaction liquid, adjust the pH<4 with hydrochloric acid, and precipitate a large amount of white solid, filter, wash with water, and dry Dry to obtain o-methoxybenzoic acid.

Embodiment 2

[0043] Add 27.0 g of 30% sodium methoxide and 0.1 mol of o-chlorobenzonitrile to a 100 ml autoclave, replace the air with nitrogen three times, seal the reactor, raise the temperature to 80°C to 100°C, and the reaction pressure is about 0.2Mpa to 0.4Mpa, and Insulate for 2 hours to 4 hours, HPLC analysis o-chlorobenzonitrile <0.5% is the end point, cool the reaction solution to less than 50°C, add 14.7g of 30% liquid alkali dropwise, heat up and distill to recover methanol, when the internal temperature reaches 100°C, Change to reflux, and keep the reflux reaction for 2 hours to 8 hours. When o-methoxybenzonitrile <0.5% is the end point, cool the reaction liquid, adjust the pH<4 with hydrochloric acid, and precipitate a large amount of white solid, filter, wash with water, and dry Dry to obtain o-methoxybenzoic acid.

Embodiment 3

[0045]Add 32.4g of 30% sodium methoxide and 0.1mol of o-chlorobenzonitrile to a 200ml autoclave, replace the air with nitrogen three times, seal the reaction kettle, raise the temperature to 130°C to 150°C, the reaction pressure is about 0.8Mpa to 1.4Mpa, and Insulate for 2 hours to 4 hours, HPLC analysis o-chlorobenzonitrile <0.5% is the end point, cool the reaction solution to less than 50°C, add 14.7g of 30% liquid alkali dropwise, heat up and distill to recover methanol, when the internal temperature reaches 100°C, Change to reflux, and keep the reflux reaction for 2 hours to 8 hours. When o-methoxybenzonitrile <0.5% is the end point, cool the reaction liquid, adjust the pH<4 with hydrochloric acid, and precipitate a large amount of white solid, filter, wash with water, and dry Dry to obtain o-methoxybenzoic acid.

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 alkali metal methoxybenzoate shown in a formula B. The preparation method comprises the following steps: 1, under the protection of inert gas, performing nucleophilic substitution reaction on a compound A and sodium methylate in methanol, wherein the reaction temperature is 80-150 DEG C and the reaction pressure is 0.18-1.4 MPa; 2, directly mixing a solution obtained in the step 1 with alkali metal hydroxide and water, removing methanol, and performing hydrolysis reaction to obtain a compound B, wherein the reaction temperature is 90-190 DEG C, and alkali metal hydroxide is sodium hydroxide and / or potassium hydroxide; performing acidification reaction on the prepared compound B and acid to prepare methoxybenzoic acid shown in a formula C. According to the method, the raw materials are easily available, a low-price safe reagent is used, and a one-pot process is adopted; the method is low in alkali consumption, little in environmental pollution, easy to perform, high in yield and suitable for industrialized production.

Description

technical field [0001] The invention relates to a preparation method of methoxybenzoic acid. Background technique [0002] O (p) methoxybenzoic acid, also known as o (p) anisic acid, is an important organic intermediate. O-methoxybenzoic acid is used to synthesize perfumes, medicines, and antiseptics; p-methoxybenzoic acid is mainly used as intermediates of amiodarone and other medicines, and can also be used in spices. [0003] The preparation methods of o (p) methoxybenzoic acid mainly include o (p) hydroxybenzoic acid method, o (p) methoxybenzaldehyde method, o (p) methoxybenzyl alcohol method, o (p) formaldehyde Oxybenzonitrile method and o (p) cresol method. [0004] 1. Ortho (p) hydroxybenzoic acid method. Using the corresponding hydroxybenzoic acid as raw material, in alkaline solution, carry out methylation reaction with dimethyl sulfate or methyl iodide, etc., the resulting sodium methoxybenzoate is finally desalted with hydrochloric acid, and can be prepared res...

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): C07C65/21C07C51/41C07C51/02
CPCC07C51/02C07C51/412C07C253/30C07C65/21C07C255/54
Inventor 樊小彬徐晓明黄超张俊涛沈启富陈宇
Owner 联化科技(上海)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