3,5-dichloro-2-pentanone preparation method

A technology of pentanone and sulfonyl chloride, which is applied in the field of preparation of 3,5-dichloro-2-pentanone, can solve the problems of complex process and non-environmental protection, and achieve the effects of simple process, avoiding three wastes and high yield

Active Publication Date: 2019-01-25
NUTRICHEM LAB CO LTD
View PDF4 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a method for preparing 3,5-dichloro-2-pentanone in order to overcome the problems of complicated and unenvironmental-friendly preparation of 3,5-dichloro-2-pentanone in the prior art, The preparation method is convenient, convenient, economical and environmentally friendly

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
  • 3,5-dichloro-2-pentanone preparation method
  • 3,5-dichloro-2-pentanone preparation method

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0008] The invention provides a preparation method of 3,5-dichloro-2-pentanone, wherein the preparation method comprises: contacting α-acetyl-γ-butyrolactone and sulfonyl chloride in a system without solvent A chlorination reaction is carried out, and then the material obtained by the chlorination reaction is mixed with water, and hydrochloric acid is added dropwise to the obtained mixture to carry out a ring-opening reaction.

[0009] According to the present invention, in order to improve the yield of 3,5-dichloro-2-pentanone and reduce production cost, preferably, in the chlorination reaction, the consumption of α-acetyl-γ-butyrolactone is the same as The molar ratio of the amount of sulfonyl chloride is 1:1-1.5, preferably 1:1-1.05.

[0010] According to the present invention, the conditions of the chlorination reaction preferably include: the reaction temperature is 0-60°C, preferably 0-20°C; the reaction time is 0.4-4h, preferably 0.5-2h. Under the preferred chlorinatio...

Embodiment 1

[0028] Add 261.5g (2mol) of α-acetyl-γ-butyrolactone to a 1000ml four-necked bottle, control the temperature at 15°C, add 281g (2.04mol) of sulfonyl chloride dropwise, the dropping rate is 4.08mol / h, continue to Stir under temperature control for 1 h until the conversion of raw materials is complete, then add 100 g of water. Then, the temperature was raised to 100° C., and 344.7 g of 36% by weight hydrochloric acid (3.4 mol of HCl) was added dropwise at a rate of 3.4 mol / h in terms of HCl. After the drop was completed, the temperature-controlled stirring was continued for 3 h. After the reaction was completed, it was lowered to room temperature, and then 500 g of 1,2-dichloroethane was added to the system for extraction and separation. The organic layer was distilled under reduced pressure to obtain 3,5-dichloro-2-pentanone with a purity of 98%. The yield is 90%.

Embodiment 2

[0030] Add 261.5g (2mol) of α-acetyl-γ-butyrolactone into a 1000ml four-necked bottle, control the temperature at 20°C, add 289g (2.1mol) of sulfonyl chloride dropwise, and the dropping rate is 2.1mol / h, continue to Stir under temperature control for 0.5 h until the conversion of raw materials is complete, then add 209 g of water. Then, the temperature was raised to 110° C., and 1217 g of 15% by weight hydrochloric acid (5 mol of HCl) was added dropwise at a rate of 2.5 mol / h in terms of HCl. After the drop was completed, the temperature-controlled stirring was continued for 6 h. After the reaction was completed, it was lowered to room temperature, and then 500 g of 1,2-dichloroethane was added to the system for extraction and separation. The organic layer was distilled under reduced pressure to obtain 3,5-dichloro-2-pentanone with a purity of 98%. The yield was 89%.

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 the field of fine chemicals, and discloses a 3,5-dichloro-2-pentanone preparation method, which comprises: making alpha-acetyl-gamma-butyrolactone contact sulfonyl chloride ina solvent-free system to carry out a chlorination reaction, mixing the material obtained by the chlorination reaction with water, adding hydrochloric acid to the obtained mixture in a dropwise manner, and carrying out a ring-opening reaction. According to the present invention, the solvent-free one-pot reaction is achieved by using the cheap industrial chemicals as the raw materials, such that the process operation is simplified, the three-waste and the production cost are reduced, and the pollution caused by the use of the metal catalyst is avoided.

Description

technical field [0001] The invention relates to the field of fine chemicals, in particular to a preparation method of 3,5-dichloro-2-pentanone. Background technique [0002] 3,5-Dichloro-2-pentanone is an important intermediate in the synthesis of pharmaceuticals and pesticides, especially in the synthesis of prothioconazole, a fungicide developed by Bayer. In 1975, it was reported that 2-methyl-2-hydroxytetrahydrofuran was used as the raw material to form the intermediate through ring-opening with hydrochloric acid and chlorination with sulfuryl chloride, but the yield of this process was relatively low, and the yield in the latter step was only 70%. In 1983, it was reported that the intermediate was obtained by photochemical addition reaction of 3-buten-2-one and dichloromethane as raw materials under the catalytic conditions of monovalent copper ions. The reaction used metal catalysts and photochemical reaction conditions , therefore, the industrialization of the process...

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): C07C45/59C07C49/16
CPCC07C45/59C07C49/16
Inventor 孙自培焦体杨红业陈笑宇李辛夷汪春华
Owner NUTRICHEM LAB CO LTD
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