Unlock instant, AI-driven research and patent intelligence for your innovation.

Synthesis method of 3,5-dichloro-2-pentanone

A synthesis method and pentanone technology are applied in the synthesis field of 3,5-dichloro-2-pentanone, which can solve the problems of only 58.8% yield and storage limitation, and achieve simplified reaction post-processing, simple operation, and easy operation. The effect of industrialized production

Inactive Publication Date: 2017-04-19
ANHUI COSTAR BIOCHEM CO LTD
View PDF2 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

At present, α'-chloro-α-acetyl-γ-butyrolactone and hydrochloric acid are commonly used to prepare 3,5-dichloro-2-pentanone in one pot under acidic conditions. In the reported literature, the reaction usually has black Coke-like substances are produced, and the yield is only 58.8%. In the literature, α'-chloro-α-acetyl-γ-butyrolactone is also chlorinated with solid phosgene. Although the three wastes are reduced in this method, the yield is the highest It reaches 81.5%, and solid phosgene is a highly toxic chemical, its storage is strictly restricted, and it is a chemical prohibited by road transportation

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
  • Synthesis method of 3,5-dichloro-2-pentanone
  • Synthesis method of 3,5-dichloro-2-pentanone
  • Synthesis method of 3,5-dichloro-2-pentanone

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0020] (1) Sulfonyl chloride nucleophilic chlorination reaction: In a 2L glass reactor equipped with mechanical stirring and a thermometer, add 640 g (5 mol) of α-acetyl-γ-butyrolactone, and cool it down to 5 ° C by ice machine circulation condensation , 708g (5.25mol) of sulfuryl chloride was added dropwise, and the dropwise addition was completed in about 2.5h. The progress of the reaction was monitored by thin-layer chromatography, and the reaction was continued at 5-10°C for 0.5h, and the raw materials were completely reacted. After the reaction, the reaction solution was poured into water, separated into layers to remove the lower organic phase, washed with water, and dried over anhydrous magnesium sulfate. Obtain 801.7 g of light yellow transparent liquid α'-chloro-α-acetyl-γ-butyrolactone, GC analysis, content 99.5%, yield 99.1%.

[0021] (2) Ring-opening reaction: In a 1000mL four-necked flask equipped with a water separator and a thermometer, add 295g (3mol) of 36-38...

Embodiment 2

[0023] (1) Sulfonyl chloride nucleophilic chlorination reaction: In a 2L glass reactor equipped with mechanical stirring and a thermometer, add 640 g (5 mol) of α-acetyl-γ-butyrolactone, and cool it down to 5 ° C by ice machine circulation condensation , 674 g (5 mol) of sulfuryl chloride was added dropwise, and the dropwise addition was completed in about 2.5 hours. The progress of the reaction was monitored by thin-layer chromatography, and the reaction was continued at 5-10°C for 0.5h, and the raw materials were completely reacted. After the reaction, the reaction solution was poured into water, separated into layers to remove the lower organic phase, washed with water, and dried over anhydrous magnesium sulfate. Obtain 756.5 g of light yellow transparent liquid α'-chloro-α-acetyl-γ-butyrolactone, GC analysis, content 96.9%, yield 95.8%.

[0024] (2) Ring-opening reaction: In a 1000mL four-necked flask equipped with a water separator and a thermometer, add 197g (2mol) of 3...

Embodiment 3

[0026] (2) Ring-opening reaction: In a 1000mL four-necked flask equipped with a water separator and a thermometer, add 394g (4mol) of 36-38% concentrated hydrochloric acid, 10.6g (0.08mol) of anhydrous aluminum trichloride, and heat up to 100 Reflux around ℃, then 1.7g (0.01mol) tetraethylammonium chloride is dissolved in the α'-chloro-α-acetyl-γ-butyrolactone 164g that step (1) obtains, (content 99.5%, 1mol) Into the solution, slowly drop into the hot hydrochloric acid dissolved in the Lewis acid catalyst, add dropwise for 6h, keep warm for 0.5h after the dropwise addition, after the reaction, cool down to room temperature, and distill the brown-red reaction solution under reduced pressure to obtain 3,5- The azeotrope of dichloro-2-pentanone and water, separate liquid, use w(NaHCO 3 ) = 5% aqueous solution, washed with water in sequence, and dried over anhydrous magnesium sulfate to obtain 142 g of 3,5-dichloro-2-pentanone light yellow-green liquid with a content of 98.5% and...

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 synthesis method of 3,5-dichloro-2-pentanone. In the method, [alpha]-acetyl-[gamma]-butyrolactone is subjected to chlorination by sulfonyl chloride. The product is then subjected to ring opening, decarboxylation and chlorination in a hot hydrochloric acid solution to prepare a crude product. The crude product then is subjected to pressure reduced distillation to obtain high-purity 3,5-dichloro-2-pentanone. In the method, a phase transfer catalyst and a Lewis acid catalyst are employed at the same time, thereby avoiding generation of black tar, accelerating the reaction and increasing the yield of chlorination of primary alcohol. The method is simple in operations and treatment, is high in yield and is suitable for industrial production.

Description

technical field [0001] The invention belongs to the field of fine chemical synthesis, and in particular relates to a synthesis method of 3,5-dichloro-2-pentanone. Background technique [0002] 3,5-Dichloro-2-pentanone is an important synthetic intermediate of organic medicine and pesticide. Not only can it be used to synthesize γ-aminobutyric acid modulator (clomethiazole), compound for inhibiting leukemia and antitumor activity (2-chloroethyl-3-methyl-5,6-dihydro-1,4-disulfide Heterocyclohexadiene, etc.), can also be used to synthesize organic pesticides (prothioconazole, etc.). At present, α'-chloro-α-acetyl-γ-butyrolactone and hydrochloric acid are commonly used to prepare 3,5-dichloro-2-pentanone in one pot under acidic conditions. In the reported literature, the reaction usually has black Coke-like substances are produced, and the yield is only 58.8%. In the literature, α'-chloro-α-acetyl-γ-butyrolactone is also chlorinated with solid phosgene. Although the three wast...

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): C07C45/59C07C49/16
CPCC07C45/59C07D307/33C07C49/16
Inventor 王红伟温兰兰傅盛辉黄会真孔顺喜杨红军
Owner ANHUI COSTAR BIOCHEM CO LTD