Method for preparing fluorophenol

A phenol and fluorine-substituted technology, which is applied in the field of preparation of trifluorophenol, can solve the problems of inconvenient process flow and post-processing, not conforming to the establishment of a conservation-oriented society, and unsuitable for industrial production, and achieves low cost, stable quality, and post-processing easy effect

Active Publication Date: 2009-06-03
QUZHOU CHEMSPEC CORP +1
View PDF2 Cites 19 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The method disclosed in the Japanese patent JP10025261A uses trifluorobromobenzene as a raw material to prepare trifluorophenol in one step. The method has poor selection and orientation, and only 70% of the obtained products are target products, which is not suitable for industrial production; Also disclosed is a kind of taking tetrafluorobenzene as raw material, utilizes phase-transfer catalyst to make the method for trifluorophenol in the next step legal system under alkaline condition, this method uses strong base NaOH and expensive phase-transfer catalyst, the technological process of reaction and Post-processing has brought a lot of inconvenience, resulting in waste of energy and resources, which is not in line with the concept of creating a conservation-oriented society
It can be seen that at present, there is no preparation method for trifluorophenol that is suitable for industrialized production and has less impact on the environment.

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 fluorophenol
  • Method for preparing fluorophenol
  • Method for preparing fluorophenol

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0033] The preparation method of fluorophenol of the present invention, take fluorobromophenyl bromobenzene as raw material, and R 4 MgCl undergoes Grignard exchange to generate fluorophenylmagnesium chloride, and then reacts with B(OR 5 ) 3 The reaction produces fluorophenylboronic acid ester, which is hydrolyzed under acidic conditions to obtain fluorophenylboronic acid. Fluorinated phenylboronic acid is oxidized with hydrogen peroxide to obtain crude fluorophenol, and the product fluorophenol is obtained after post-treatment, and its content is >99.9%. The present invention prepares the Grignard reagent of fluorobromobenzene by Grignard exchange reaction, improves the conversion rate, reduces the impurity content in the Grignard reagent, obtains the Grignard reagent of high-purity fluorobromobenzene, thereby greatly improves The purity and yield of the final product.

[0034] Beneficial effects of the present invention: the preparation method of fluorophenol of the prese...

Embodiment 1

[0037] Example 1 Preparation of i-PrMgCl

[0038] 69g (2.89mol) of Mg and 200ml THF were added to a 2000ml four-necked flask, and a mixed solution of 216g i-PrCl (2.75mol) and 770ml THF was added dropwise at 30°C under stirring. After the dropwise addition, stir for 0.5 to 1 hour and keep warm for later use.

Embodiment 2

[0039] Example 2 Preparation of 3,4,5-trifluorophenylboronic acid

[0040] Add 527.5g of 3,4,5-trifluorobromobenzene (2.5mol) and 1100ml of THF into a 5000ml four-neck flask, stir for 15min, cool down to -20°C and add i-PrMgCl dropwise, after the dropwise addition, keep stirring for 2h, dropwise add 286g of trimethyl borate (2.75mol), keep warm for 2 hours after the dropwise addition, add 365g of 30% HCl dropwise, keep warm for 2 hours after the dropwise addition, evaporate THF, add 600ml of EtOAc and 500ml of water to dissolve and separate the liquid, and extract the water phase with 200ml of EtOAc The organic phases were combined, EtOAc was distilled off, and 350 ml of n-hexane was beaten to obtain 350 g of 3,4,5-trifluorophenylboronic acid with a content of 99.8% and a yield of 79.5%. The boiling point is 132°C / 20mmHg.

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 provides a method for preparing fluorophenol. Fluorobromobenzene is used as raw material to take Grignard exchange reaction with R4MgCl to generate difluorophenyl magnesium chloride and then react with B(OR5)3 to generate fluorophenol boric acid ester, and the fluorophenol boric acid ester is hydrolyzed under an acid condition to generate fluorophenol boric acid. The fluorophenol boric acid is oxidized to generate crude fluorophenol to be carried out post treatment to get a product of the fluorophenol. The invention prepares Grignard reagent of the fluorobromobenzene by the Grignard exchange reaction, thereby improving the purity and the yield of the final product greatly.

Description

technical field [0001] The invention relates to the field of a preparation method of fluorophenol, in particular to the field of a preparation method of trifluorophenol. Background technique [0002] Trifluorophenol is an important chemical intermediate, which is mainly used in the preparation of electronic chemicals and pharmaceutical intermediates. The traditional process is to prepare Grignard reagent from trifluorobromobenzene and then react with borate ester to generate trifluorophenylboronic acid, and then React with hydrogen peroxide to produce trifluorophenol. Its disadvantages are that a large amount of solvent is used in industrial production, post-treatment is difficult, and more waste water is generated; the total reaction yield is low and the unit consumption is large. The method used in the Chinese patent CN1861554A is to use 1-halo-3,4,5-trifluorobenzene as the starting material, and sequentially undergo ammoniation, diazotization, and hydrolysis to obtain tr...

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): C07C39/27C07C37/60
Inventor 李功勇罗贵文江向阳张文明陈金华
Owner QUZHOU CHEMSPEC CORP
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