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

Synthesis method of 1,2,4-trifluoro benzene

A synthesis method and technology of trifluorobenzene, applied in chemical instruments and methods, preparation of halogenated hydrocarbons, organic chemistry, etc., can solve the problems of unsatisfactory product purity, harsh reaction conditions, and high price, and achieve less impurities and better operating conditions The effect of stability and simplified operation

Active Publication Date: 2013-12-11
ZHEJIANG ZHONGXIN FLUORIDE MATERIALS CO LTD
View PDF7 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0022] Although the method has easy-to-obtain raw materials and simple synthesis steps, it is expensive and difficult to obtain because the catalyst used is a special catalyst. At the same time, the reaction conditions are very harsh and the product purity is not ideal.

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
  • Synthesis method of 1,2,4-trifluoro benzene

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0069] Add 166 grams of 30% methylamine aqueous solution into a 500 ml reaction bottle, stir at room temperature, add 114.4 grams of tetrachlorophthalic anhydride (I) in batches, and after the addition is completed, heat up to 40-50 o C was reacted for 3 hours and cooled to room temperature to obtain compound (II).

[0070] To the above-mentioned system containing compound (II), add 240 grams of 20% sodium hydroxide solution, stir and cool to -10~0 o C, add 65 grams of zinc powder, temperature control -10 ~ 0 o C reacted for 20 hours, removed the low-temperature bath, returned to room temperature, filtered, and washed the filter cake with water. The filtrate and the washing liquid were combined, the pH was adjusted to acidic with concentrated hydrochloric acid, filtered, and the filter cake was drained to obtain a mixture of compound (III') and compound (III"), with a wet weight of 102 grams.

[0071] In a 500 ml reaction flask, add the mixture of the above compound (I...

Embodiment 2

[0077] Add 155 grams of 40% methylamine aqueous solution in 1 liter reaction bottle, stir and cool to 10 o C, add 286 grams of tetrachlorophthalic anhydride (I) in batches, after adding, control the temperature for 10-20 o C was reacted for 6 hours to obtain compound (II).

[0078] To the above system containing compound (II), add 530 g of 15% sodium hydroxide solution, stir at room temperature, add 130 g of zinc powder, react at room temperature for 10 hours, filter, and wash the filter cake with water beating. Combine the filtrate and the washing liquid, adjust the pH to acidic with concentrated hydrochloric acid, filter, and drain the filter cake to obtain a mixture of compound (III') and compound (III"), with a wet weight of 260 grams.

[0079] In a 1-liter reaction flask, add the mixture of the above-mentioned compound (III') and compound (III"), add 130 grams of toluene, 650 grams of sulfolane, reflux for 15 hours, distill the toluene off, and cool down to room temp...

Embodiment 3

[0085] Add 186 grams of 35% methylamine aqueous solution into a 1-liter reaction bottle, stir at room temperature, add 200 grams of tetrachlorophthalic anhydride (I) in batches, and react at room temperature for 5 hours to obtain compound (II).

[0086] To the above-mentioned system containing compound (II), add 350 grams of 12% sodium hydroxide solution, and control the temperature for 10 to 20 o C, add 68.5 grams of zinc powder, after adding, in 10 ~ 20 o C was reacted for 15 hours. Filter, wash the filter cake twice with 50 g of 1% sodium hydroxide solution, combine the filtrate and washing liquid, adjust the pH to acidic with concentrated hydrochloric acid, filter, and drain the filter cake to obtain compound (III') and compound (III" ) with a wet weight of 168 grams.

[0087] In a 1-liter reaction flask, add the mixture of the above-mentioned compound (III') and compound (III"), add 380 grams of toluene, 420 grams of sulfolane, reflux for 18 hours, distill out the...

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 synthesis method of 1,2,4-trifluoro benzene, and belongs to the technical field of chemical synthesis. The synthesis method is characterized by comprising the following reaction steps that (1) tetrachloro phthalic anhydride reacts with a methylamine aqueous solution, and 6-carboxyl-2,3,4,5-tetrachlorobenzene formyl methylamine is obtained; (2) 6-carboxyl-2,3,4,5-tetrachlorobenzene formyl methylamine reacts with zinc powder, and a mixture of 6-carboxyl-2,3,5-trichloro benzene formyl methylamine and 6-carboxyl-2,4,5-trichloro benzene formyl methylamine is obtained; (3) the mixture of 6-carboxyl-2,3,5-trichloro benzene formyl methylamine and 6-carboxyl-2,4,5-trichloro benzene formyl methylamine is subjected to backflow water diversion cyclization in sulfolane and toluene, and a mixture of 3,4,6-trichloro phthalic methylamine and sulfolane is obtained; (4) the mixture of 3,4,6-trichloro phthalic methylamine and sulfolane reacts with potassium fluoride, and 3,4,6-trifluoro phthalic methylamine is obtained; (5) 3,4,6-trifluoro phthalic acid is obtained by hydrolyzing 3,4-6-trifluoro phthalic methylamine; and (6) 1,2,4-trifluoro benzene is obtained by decarboxylizing 3,4,6-trifluoro phthalic acid. The synthesis method has the advantages that a raw material is easy to obtain; the method is easy and simple to operate; the purity of a product is good; and the method has a higher industrial application value.

Description

[0001] Technical field: [0002] The invention belongs to the technical field of chemical synthesis, and in particular relates to a synthesis method of 1,2,4-trifluorobenzene. [0003] Background technique: [0004] 1,2,4-Trifluorobenzene is an important pharmaceutical intermediate used in the synthesis of Sitagliptin, a drug for treating diabetes. At present, there are not many reports on the synthesis route of 1,2,4-trifluorobenzene at home and abroad, mainly as follows: [0005] (1) Using difluoroaniline as raw material, 1,2,4-trifluorobenzene was synthesized by diazotization and Schiemann reaction: [0006] For example, CN102643160 uses 2,4-difluoroaniline as raw material to synthesize 1,2,4-trifluorobenzene. [0007] . [0008] Another example is CN101817724, which uses 3,4-difluoroaniline as a raw material to synthesize 1,2,4-trifluorobenzene. [0009] . [0010] Although this method has shorter reaction steps, the price of starting materials is more expens...

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): C07C25/13C07C17/363
Inventor 袁其亮杨燕施正军陈寅镐王超
Owner ZHEJIANG ZHONGXIN FLUORIDE MATERIALS CO LTD
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