Check patentability & draft patents in minutes with Patsnap Eureka AI!

Method for synthesizing ethyl alpha-bromoisobutyrate

A technology of ethyl bromoisobutyrate and bromoisobutyric acid, which is applied in the field of synthesis of fine chemical intermediate α-ethyl bromoisobutyrate, can solve the problem of high risk, strong corrosion and inability to use bromine Solve problems such as high quality, achieve the effect of improving utilization rate, improving safety, and good appearance quality

Inactive Publication Date: 2018-12-14
XINCHANG COUNTY TAIRU TECH CO LTD
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0011] 1. The use of bromine as the raw material for the bromination reaction has the problems of high toxicity, poor production environment, and low utilization rate of bromine atoms;
[0012] 2. The esterification reaction uses concentrated sulfuric acid as a catalyst, which has the problems of strong corrosion, poor selectivity and great danger
However, the 7 types of catalysts introduced cannot utilize the residual bromine more or less present in the bromination reaction solution in the esterification reaction of α-bromoisobutyric acid and ethanol, and cannot solve the problem of α-bromine caused by the presence of bromine in the reaction solution. - The problem of yellowish color of ethyl bromoisobutyrate

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 synthesizing ethyl alpha-bromoisobutyrate
  • Method for synthesizing ethyl alpha-bromoisobutyrate
  • Method for synthesizing ethyl alpha-bromoisobutyrate

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0044]In a 500ml four-necked flask with a stirring blade and a thermometer, successively put isobutyric acid: 35.5g (content: 99.0%, 0.3994mol), cyclohexane: 300ml (about 230g), dibenzoyl peroxide 0.25g, N-bromosuccinimide: 75.6 g (content: 98.8%, 0.4196 mol). Fix the water separator on the four-neck flask, and fix the condenser on the upper part of the water separator. Turn on the stirring and set the stirring speed above 500r / min. The outer wall of the four-necked bottle is heated with a water bath, and the temperature of the hot water in the water bath is set at 90°C. When the internal temperature of the four-necked bottle reaches about 82°C, the inside of the reaction bottle starts to boil and vaporize, and the vaporized cyclohexane dissolves a small amount of water in the reaction system. Take out the reaction vial and settle to the bottom of the trap.

[0045] As the reaction proceeds, the reaction feed liquid gradually changes from colorless to light yellow, and the N...

Embodiment 2

[0051] In a 500ml four-necked flask with a stirring blade and a thermometer, successively put isobutyric acid: 35.0g (content: 99.0%, 0.3938mol), cyclohexane: 380ml (about 300g), dibenzoyl peroxide 0.24g, N-bromosuccinimide: 75.7 g (content: 98.8%, 0.4202 mol). Fix the water separator on the four-neck flask, and fix the condenser on the upper part of the water separator. Turn on the stirring and set the stirring speed above 500r / min. The outer wall of the four-necked bottle is heated with a water bath, and the temperature of the hot water in the water bath is set at 90°C. When the internal temperature of the four-necked bottle reaches about 82°C, the inside of the reaction bottle starts to boil and vaporize, and the vaporized cyclohexane dissolves a small amount of water in the reaction system. Take out the reaction vial and settle to the bottom of the trap.

[0052] As the reaction proceeds, the reaction feed liquid gradually changes from colorless to light yellow, and the ...

Embodiment 3

[0058] In a 500ml four-necked flask with a stirring blade and a thermometer, successively put isobutyric acid: 35.0g (content: 99.0%, 0.3938mol), benzene: 380ml (about 330g), dibenzoyl peroxide 0.25g, N- Bromosuccinimide: 76.0 g (content: 98.8%, 0.4218 mol). Fix the water separator on the four-neck flask, and fix the condenser on the upper part of the water separator. Turn on the stirring and set the stirring speed above 500r / min. The outer wall of the four-necked bottle is heated with a water bath, and the temperature of the hot water in the water bath is set at 90°C. When the internal temperature of the four-necked bottle reaches about 82°C, the inside of the reaction bottle starts to boil and vaporize, and the vaporized cyclohexane dissolves a small amount of water in the reaction system. Take out the reaction vial and settle to the bottom of the trap.

[0059] As the reaction proceeds, the reaction feed liquid gradually changes from colorless to light yellow, and the N-b...

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 method for synthesizing ethyl alpha-bromoisobutyrate. The ethyl alpha-bromoisobutyrate is synthesized by using isobutyric acid as a starting material through bromination andesterification. N-bromosuccinimide or N-bromophthalimide is used as a bromination reagent in the bromination, so as to improve the utilization of bromine atoms and improve the safety of the process; the esterification is catalyzed by a double catalytic system, and the zinc powder added and the trace bromine of the bromination form ZnBr2 as a catalyst for the esterification, so the scheme has fewerside reactions, low corrosion, high selectivity and good product appearance quality.

Description

technical field [0001] The invention relates to the field of fine organic chemical synthesis, in particular to the synthesis of ethyl α-bromoisobutyrate, a fine chemical intermediate. Background technique [0002] α-Bromoisobutyric acid ethyl ester (2-bromoisobutyric acid ethyl ester; 2-bromo-2-methylpropionic acid ethyl ester) English name: Ethyl2-bromoisobutyrate (2-Bromoisobutyric acid ethyl ester) is a Important chemical and pharmaceutical intermediates are widely used in the synthesis of various polymer materials and pharmaceutical products. The chemical synthesis reaction equation of ethyl α-bromoisobutyrate is as follows: [0003] 1. Bromination reaction: [0004] [0005] 2. Esterification reaction: [0006] [0007] Firstly, isobutyric acid and bromine undergo bromination reaction to synthesize α-bromoisobutyric acid; then, α-bromoisobutyric acid and ethanol undergo esterification reaction under the catalysis of strong acid such as concentrated sulfuric acid...

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): C07C51/363C07C53/19C07C67/08C07C69/63
CPCC07C51/363C07C67/08C07C53/19C07C69/63
Inventor 赵德英
Owner XINCHANG COUNTY TAIRU TECH CO LTD
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