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

Preparation method of 2-bromothiophene

A bromothiophene and thiophene technology is applied in the field of preparation of fine chemical products, and can solve the problems of not revealing the 2-position substitution selectivity of thiophene and reducing the generation amount of 3-bromothiophene.

Active Publication Date: 2020-10-13
ZHEJIANG LIAOYUAN PHARM CO LTD
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The method is environmentally friendly and the production cost is low, but the patent does not disclose a method for improving the 2-position substitution selectivity of thiophene and reducing the amount of 3-bromothiophene generated

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 2-bromothiophene
  • Preparation method of 2-bromothiophene
  • Preparation method of 2-bromothiophene

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0028] Add 52.8g (0.513mol) of commercially available sodium bromide, 7.4g (0.056mol) of commercially available L-valine methyl ester, and 340ml of water into a 500ml reaction bottle. Sulfuric acid 64.3g (0.642mol), after dropwise addition, cool down to 5-10°C, add 45.0g (0.535mol) of thiophene, then add 62.4g (0.642mol) of 35% hydrogen peroxide dropwise at 5-10°C, about 1-10°C 2 hours to drip. After dropping, control the temperature at 5-10°C for 18 hours, let stand, and separate layers. The organic layer was steam distilled to obtain 2-bromothiophene, wherein the content of 3-bromothiophene was 0.12%, see Figure 4 .

Embodiment 2

[0030] Drop into 400g of valsartan waste water in the 500ml reaction bottle, contain sodium bromide 52.8g (0.513mol), L-valine methyl ester 7.4g (0.056mol) in the waste water, control feed liquid temperature ≤ 40 ℃ under stirring, drop Add 64.3g (0.642mol) of concentrated sulfuric acid, after the dropwise addition, cool down to 5-10°C, add 45.0g (0.535mol) of thiophene, and then add 62.4g (0.642mol) of 35% hydrogen peroxide dropwise at 5-10°C, approx. 1 to 2 hours to drop. After dropping, control the temperature at 5-10°C for 18 hours, let stand, and separate layers. The organic layer was steam-distilled to obtain 2-bromothiophene, wherein the content of 3-bromothiophene was 0.14%, see Figure 5 .

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 2-bromothiophene, relates to a method for improving thiophene 2-site substitution selectivity and reducing the generation amount of 3-bromothiophene, and belongs to the technical field of preparation of fine chemical products such as medicines. The method is characterized in that thiophene is converted into 2-bromothiophene in the presence of L-valine methyl ester. The preparation method comprises the steps of adding sodium bromide, L-valine methyl ester and water, adding sulfuric acid, adding thiophene, and adding hydrogen peroxide. The reactionformula is shown in the attached drawing. The method has the advantages of being high in thiophene 2-sit substitution selectivity, small in 3-bromothiophene generation amount, environmentally friendly and low in cost.

Description

technical field [0001] A method for preparing 2-bromothiophene relates to a method for improving the 2-position substitution selectivity of thiophene and reducing the amount of 3-bromothiophene produced, and belongs to the technical field of preparation of fine chemical products such as medicine. Background technique [0002] 2-bromothiophene has important uses in the field of medicine and chemical industry: 2-thiophenethanol can be synthesized by using 2-bromothiophene as raw material through Grignard reaction and Grignard reagent conversion. 2-Thiphenethanol is an important intermediate in the synthesis of clopidogrel bisulfate. [0003] The most critical impurity of 2-bromothiophene is 3-bromothiophene. Such as figure 1 Shown: 3-bromothiophene can be transferred to the raw material drug clopidogrel bisulfate through the related reactions of the synthesis of clopidogrel bisulfate. The impurity B of the European Pharmacopoeia of clopidogrel bisulfate is transferred from ...

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): C07D333/28
CPCC07D333/28
Inventor 潘元兴王小强肖兵黄兴
Owner ZHEJIANG LIAOYUAN PHARM 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