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

Method for preparing 2,4,5 trifluorobenzene acetic acid

A technology of trifluorophenylacetic acid and trifluorobenzene, which is applied in two fields, can solve the problems of long steps, unstable Grignard reagents, and large pollution, and achieve the effects of mild reaction conditions, low reagent prices, and avoiding potential safety hazards

Active Publication Date: 2007-12-26
ZHEJIANG YONGTAI TECH CO LTD
View PDF3 Cites 28 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

U.S. Patent No. 6,870,067 reported that bromotrifluorobenzene condenses with allyl bromide after being converted into Grignard reagent, and then obtains trifluorophenylacetic acid through catalytic oxidation. The Grignard reagent in this method is unstable, and the catalyst used and oxidizing agents are more expensive
In Chinese patent CN1749232A, trifluorobenzene is first chloromethylated, then cyanided, and finally hydrolyzed to obtain trifluorophenylacetic acid. This method has long steps, low yield, and large pollution, and the highly toxic substance sodium cyanide used There are serious security risks

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 preparing 2,4,5 trifluorobenzene acetic acid
  • Method for preparing 2,4,5 trifluorobenzene acetic acid

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0011] (1) Preparation of 2,4,5-trifluorobenzyl chloride

[0012] Add 120 mL of hydrochloric acid, 70 g of zinc chloride and 31.2 g of paraformaldehyde (1.04 mol) into a three-necked flask, add 106 g (0.8 mol) of 1,2,4-trifluorobenzene with stirring at room temperature, and keep the reaction for 5 hours. Separate the organic phase, wash with water until it is neutral, and distill under reduced pressure to obtain 98.5 g of 2,4,5-trifluorobenzyl chloride with a content of 99% and a yield of 68%.

[0013] The reaction equation is:

[0014]

[0015] (2) Preparation of 2,4,5-trifluorophenylacetic acid

[0016] Add 35mL of the methanol solution of sodium cobalt tetracarbonyl (8.8mmol) into the reactor that has already contained 150mL of methanol, seal the reactor and fill with CO gas, and pump 100 grams (0.55mol) when the temperature reaches 40℃. , 5-trifluorobenzyl chloride and 120 grams of 40% sodium hydroxide solution, the reaction is maintained for 2 hours. Add 300 mL of water, di...

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

This invention provides a method for preparing 2, 4, 5-trifluorophenylacetic acid. The method comprises: (1) reacting 1,2,4-trifluorobenzene and chlorinating agent in paraformaldehyde to obtain 2,4,5-trifluorobenzyl chloride; (2) performing carbonylation reaction with CO in the presence of catalyst to obtain 2,4,5-trifluorophenylacetic acid. The catalyst is alkali cobalt tetracarbonyl. The method has such advantages as few reaction procedures, and mild reaction conditions, and is suitable for industrial production of 2, 4, 5-trifluorophenylacetic acid.

Description

Technical field [0001] The invention relates to a method for preparing 2,4,5-trifluorophenylacetic acid. Background technique [0002] Dipeptidyl peptidase-IV (DP-IV or DPP-IV) enzyme inhibitor drugs are used to treat diabetes, especially non-insulin-dependent (type II) diabetes. And 2,4,5-trifluorophenylacetic acid is an important intermediate for the synthesis of new drugs such as dipeptidyl peptidase-IV enzyme inhibitors. In the US patent application US 2004,068,141, bromotrifluorobenzene is condensed with malonic acid diester catalyzed by cuprous chloride under alkaline conditions, followed by hydrolysis to obtain trifluorophenylacetic acid, but this method is not suitable for industrial production. US patent US 6,870,067 reported that bromotrifluorobenzene was condensed with allyl bromide after being converted into Grignard reagent, and then subjected to catalytic oxidation to obtain trifluorophenylacetic acid. The Grignard reagent in this method is unstable and the catalyst...

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): C07C57/58C07C51/10
Inventor 钟建新何人宝
Owner ZHEJIANG YONGTAI TECH 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