Method for preparing dimethyl n-butyl malonate

A technology of n-butyl dimethyl malonate and dimethyl malonate, which is applied in the field of n-butyl dimethyl malonate to prepare dimethyl n-butyl malonate, can solve the problem of high cost, Difficult product separation, complex preparation methods and other problems, to achieve the effect of low cost, simple operation, and easy to achieve reaction conditions

Inactive Publication Date: 2014-09-10
SHANGHAI INST OF TECH
View PDF1 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] For the defects in the above-mentioned prior art, the technical problem to be solved by this invention is to provide a kind of method for preparing dimethyl n-butylmalonate, and this described method will solve the preparation method technology in the prior art Complexity, high cost, and difficult technical problems in product separation

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 dimethyl n-butyl malonate
  • Method for preparing dimethyl n-butyl malonate

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0021] 264.22g (227.78ml, 2.0mol) dimethyl malonate, 231.43g (260.03ml, 2.5mol) chlorobutane, 131.29g (0.95mol) anhydrous potassium carbonate powder, 438.55g (464.4ml, 6.0 mol) DMF, added to a three-necked flask, equipped with a condensing reflux device, a thermometer, heated and stirred, and the reaction temperature was 110-120°C. After reacting for 2 hours, in order to maintain the concentration of n-chlorobutane in the reaction, 185.14g (208.02 ml, 2.0mol) of n-chlorobutane was added to the reaction solution. The reflux reaction was continued for 3 hours, and 2.58 g (0.008 mol) of tetrabutylammonium bromide TBAB was added slowly, and the addition was completed in half an hour.

[0022] After adding the phase transfer catalyst, continue the reaction and track the reaction with GC, when the conversion rate of dimethyl malonate can reach 90% (GC analysis after about 6 hours). The reaction mixture was distilled off chlorobutane at 110-120°C, cooled, filtered, and the filtrate ...

Embodiment 2

[0025] 264.22g (227.78ml, 2.0mol) dimethyl malonate, 185.14g (208.02ml, 2.0mol) chlorobutane, 165.84g (1.20mol) anhydrous potassium carbonate powder, 511.64g (541.3ml, 7.0 mol) DMF, added to a three-necked flask, equipped with a condensing reflux device, a thermometer, heated and stirred, and the reaction temperature was 110-120°C. After reacting for 2 hours, in order to maintain the concentration of n-chlorobutane in the reaction, 231.43g (260.03ml, 2.5mol) of n-chlorobutane was added to the reaction solution. The reflux reaction was continued for 3 hours, and 2.58 g (0.008 mol) of tetrabutylammonium bromide TBAB was added slowly, and the addition was completed in half an hour.

[0026] After adding the phase transfer catalyst, continue the reaction and track the reaction with GC, when the conversion rate of dimethyl malonate can reach 90% (GC analysis after about 6 hours). The reaction mixture was distilled off chlorobutane at 110-120°C, cooled, filtered, and the filtrate w...

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

PropertyMeasurementUnit
refractive indexaaaaaaaaaa
Login to view more

Abstract

The invention relates to a method for preparing dimethyl n-butyl malonate, which comprises the following steps: weighing dimethyl malonate, an alkylation reagent, an inorganic alkali and a solvent, adding the dimethyl malonate and alkylation reagent into a reactor, adding the inorganic alkali and solvent, continuing stirring to react under heating reflux, supplementing chlorinated n-butane, adding a phase-transfer catalyst, continuing the reflux reaction, and collecting the product distilled at 110 DEG C under the pressure of 8 mmHg, thereby obtaining the dimethyl n-butyl malonate. The chlorinated n-butane is added in multiple steps to enhance the conversion rate of the dimethyl malonate; and after the chlorinated n-butane is recovered, fractionation is performed to obtain the product dimethyl n-butyl malonate. The method is economic and environment-friendly, has the advantages of low cost, no generation of disubstituted impurities and accessible reaction conditions, and is simple to operate and convenient for industrial production.

Description

technical field [0001] The invention belongs to the field of chemical engineering, and relates to a kind of dimethyl n-butylmalonate, in particular to a method for preparing dimethyl n-butylmalonate. Background technique [0002] Dimethyl n-butylmalonate (I), the English name is Dimethyl n-butylmalonate, [0003] [0004] (I) [0005] Colorless liquid with fruity aroma. Soluble in methanol, ethanol, ether and other organic solvents, insoluble in water. The relative density is 1.02, the boiling point is 219.6℃ / 760mmHg, and the refractive index is 1.425. Dimethyl n-butylmalonate is an important organic chemical raw material. Like its homologue diethyl n-butylmalonate, it is widely used in industries such as electrical chemicals, spices, medicine, and pesticides. In use, when used as a reaction intermediate, its superiority is far greater than that of diethyl n-butyl malonate, and the market prospect is extremely broad. [0006] At present, there are many documents on...

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): C07C69/46C07C67/343
CPCC07C67/343C07C69/46
Inventor 欧文华
Owner SHANGHAI INST OF TECH
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