Supercharge Your Innovation With Domain-Expert AI Agents!

Method for preparing 3-amino-4-fluorophenol

A technology of fluorophenol and fluorophenol ester, which is applied in the field of preparation of 3-amino-4-fluorophenol, can solve the problems of difficult preparation of raw materials, difficult reaction control, and low selectivity, and achieves less side reactions, low cost, The effect of mild reaction conditions

Inactive Publication Date: 2009-09-02
滨海康杰化学有限公司 +1
View PDF0 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This shows, the raw material itself of above-mentioned preparation method is very difficult to make, and reaction is difficult to control, and selectivity is low, and by-product is many, and productive rate is very low

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 3-amino-4-fluorophenol
  • Method for preparing 3-amino-4-fluorophenol

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0041] The preparation of embodiment 1 3-amino-4-fluorophenol

[0042] (1) Preparation of 2-bromo-4-fluorophenol:

[0043] Add 200g (1.785mol) of p-fluorophenol and 300ml of dichloroethane into a 2L reaction bottle, and after mixing, add dropwise a mixture of 300g (1.875mol) of bromine and 150ml of dichloroethane at 5°C to 10°C. Afterwards, keep warm for half an hour. Then add 33g (0.26mol) sodium sulfite and 200ml water mixed solution, stir for 30min, let stand to separate layers, take the organic layer, wash with mixed lye (10%NaOH / 20%NaHCO 3) to neutral, dried over anhydrous magnesium sulfate, and the solvent was evaporated by a rotary evaporator to obtain 343 g (1.688 mol) of yellow liquid 2-bromo-4-fluorophenol. Molar yield: 95%, the purity determined by gas chromatography is 94%. The boiling point is 145°C / 20mmHg.

[0044] (2) Preparation of ethyl 2-bromo-4-fluorophenoxyformate

[0045] Add 74.3g of sodium hydroxide (1.857mol) and 675ml of water into a 2L reaction f...

Embodiment 2

[0052] Example 2 Preparation of 3-amino-4-fluorophenol

[0053] (1) Preparation of 2-bromo-4-fluorophenol

[0054] Add 200g (1.785mol) of p-fluorophenol and 361g (2.142mol) of 48% hydrobromic acid into a 2L reaction bottle, mix and add 269.5g (2.142mol) of 27% H 2 o 2 After dripping, heat preservation reaction for half an hour, then add 45g (0.357mol) sodium sulfite, stir for 30min, let stand for layering, take the organic layer and use mixed lye (10%NaOH / 20%NaHCO 3 ) to neutral, and dried over anhydrous magnesium sulfate to obtain a yellow liquid. The boiling point is 145°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 relates to a method for preparing 3-amino-4-fluorophenol, which comprises the following steps: (1) halogenating 2-position of 4-fluorophenol; (2) esterifying 2-halogen-4-fluorophenol to obtain 2-halogen-4-fluorophenol ester; (3) nitrifying 5-position of the 2-halogen-4-fluorophenol ester to obtain 2-halogen-4-fluorine-5-nitrophenol ester; and (4) reducing, hydrolyzing and dehalogenating the obtained 2-halogen-4-fluorine-5-nitrophenol ester to obtain the 3-amino-4-fluorophenol. The method has the advantages of short synthetic route, moderate conditions, easy industrialization, and the like, and an obtained target product has high purity, less single impurities and stable quality, and completely meets the requirement of being used as an intermediate.

Description

technical field [0001] The present invention relates to a kind of preparation method of 3-amino-4-fluorophenol Background technique [0002] 3-Amino-4-fluorophenol is a commonly used organic chemical intermediate, and is commonly used in the synthesis of liquid crystal compounds, pharmaceutical compounds and pesticide compounds. [0003] There are several methods for preparing phenol, and the commonly used methods for introducing hydroxyl groups are: [0004] 1) Halide hydrolysis [0005] 2) Aromatic sulfonate alkali fusion [0006] 3) Hydrolysis of primary arylamine and diazonium salt [0007] 4) A method for preparing alcohols and phenolic compounds through nucleophilic substitution reactions such as direct introduction of hydroxyl groups onto aromatic rings. [0008] According to the record of document Jpn.Kokai Tokkyo Koho, 60064960, 13 Apr 1985, Showa, the preparation method of 3-amino-4-fluorophenol can be represented by following reaction equation: [0009] ...

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): C07C213/02C07C215/76
Inventor 李功勇唐伟蒙徐向荣
Owner 滨海康杰化学有限公司
Features
  • R&D
  • Intellectual Property
  • Life Sciences
  • Materials
  • Tech Scout
Why Patsnap Eureka
  • Unparalleled Data Quality
  • Higher Quality Content
  • 60% Fewer Hallucinations
Social media
Patsnap Eureka Blog
Learn More

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2025 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com