Synthetic method for 2-benzyl cyclopentanone

A technology of benzylcyclopentanone and a synthesis method is applied in the field of preparation of organic pharmaceutical intermediates, and can solve the problems of sodium amide easily causing fire, low total product yield, useless by-products, etc. cost, waste reduction effect

Active Publication Date: 2014-01-15
KUNSHAN RIKITA PHARMA
View PDF0 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0014] Method 3) The total yield of the product is low, sodiu

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
  • Synthetic method for 2-benzyl cyclopentanone
  • Synthetic method for 2-benzyl cyclopentanone
  • Synthetic method for 2-benzyl cyclopentanone

Examples

Experimental program
Comparison scheme
Effect test

Example Embodiment

[0044] Example 1:

[0045] 1) Friedel-Crafts acylation and esterification reaction (synthesis of 5-benzoylvalerate methyl ester, ROH=CH30H):

[0046] Add 80ml of benzene and 0.22mol of aluminum trichloride into the reaction flask, add 0.1mol of adipic anhydride (dissolved in 20ml of benzene) dropwise at 31~55℃, then react at 40~55℃ for 2 hours, add 0.5mol methanol dropwise, Continue to react at 40-55°C for 2 hours, add the reaction mixture to 200ml of water to hydrolyze, statically separate the layers, wash the benzene layer with sodium carbonate aqueous solution, distill out benzene at 100°C, and the residue is 5-benzoylvalerate methyl Ester, the product is light yellow, the freezing point is 35-36.5°C, the content is above 98%, and the yield is 90-92%.

[0047] 2) Condensation and cyclization reaction (synthesis of 2-benzoylcyclopentanone, tripotassium phosphate method) 0.1mol of 5-benzoylvalerate methyl ester, 0.1mol of tripotassium phosphate and 50ml of DMF are refluxed for ...

Example Embodiment

[0050] Example 2:

[0051] 1) Friedel-Crafts acylation and esterification reaction (synthesis of methyl 5-benzoylvalerate, ROH=CH3OH):

[0052] Add 80ml of benzene and 0.22mol of aluminum trichloride into the reaction flask, add 0.1mol of adipic anhydride (dissolved in 20ml of benzene) dropwise at 31~55℃, then react at 50-70℃ for 2 hours, add 0.5mol methanol dropwise, Continue to react at 50-70°C for 2 hours, add the reaction mixture to 200ml of water to hydrolyze, then separate the layers at rest, wash the benzene layer with sodium carbonate aqueous solution, distill off benzene at 100°C, and the residue is 5-benzoylvalerate methyl Ester, the product is light yellow, the freezing point is 35-36.5°C, the content is above 98%, and the yield is 90-92%.

[0053] 2) Condensation and cyclization reaction (synthesis of 2-benzoylcyclopentanone, triethylamine method)

[0054] Put 0.1mol of 5-benzoylvalerate methyl ester, 0.1mol of triethylamine and 50ml of DMF into the autoclave,

[0055] ...

Example Embodiment

[0058] Example 3:

[0059] 1) Friedel-Crafts acylation and esterification reaction (synthesis of 5-benzoylvalerate methyl ester):

[0060] Add 80ml of benzene and 0.3mol of aluminum trichloride to the reaction flask, add 0.1mol of adipic anhydride (dissolved in 20ml of benzene) dropwise at 31~55℃, then react at 60~75℃ for 2 hours, add 0.4mol of ethanol dropwise, Continue to react at 60~75℃ for 2 hours, add the reaction mixture to 200ml of water to hydrolyze, then separate the layers at rest, wash the benzene layer with sodium carbonate aqueous solution, distill benzene out at 100℃, and the residue is 5-benzoylvalerate methyl Ester, the product is light yellow, the freezing point is 35-36.5°C, the content is above 98%, and the yield is 90-92%.

[0061] 2) Condensation and cyclization reaction (synthesis of 2-benzoylcyclopentanone, tripotassium phosphate method) 0.2mol of 5-benzoylvalerate methyl ester, 0.2mol of tripotassium phosphate and 1000ml of DMF are refluxed for 12 hours....

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
Freezing pointaaaaaaaaaa
Freezing pointaaaaaaaaaa
Freezing pointaaaaaaaaaa
Login to view more

Abstract

The invention discloses a synthetic method for 2-benzyl cyclopentanone. Benzene and adipic anhydride are subjected to Friedel-Crafts and esterification one-pot reaction to synthesize 5-benzoylpentanoic acid ester, 5-benzoylpentanoic acid ester is subjected to acyloin ester condensation and cyclization reactions to produce 2-benzoyl cyclopentanone, and 2-benzoyl cyclopentanone is subjected to selective hydrogenation reduction reaction to obtain the 2-benzyl cyclopentanone product. According to the invention, 2-benzyl cyclopentanone can be synthesized at a low cost, waste emission is reduced and the yield of 2-benzyl cyclopentanone is improved.

Description

[0001] technical field [0002] The invention relates to a method for preparing an organic drug intermediate, in particular to a method for synthesizing 2-benzylcyclopentanone. Background technique [0003] 2-benzylcyclopentanone is an organic pharmaceutical intermediate, which can be used for the synthesis of loxoprofen, a non-steroidal anti-inflammatory analgesic. The methods are: [0004] 1) Alkylation and decarboxylation of benzyl chloride and 2-methoxycarbonyl cyclopentanone, the total yield is about 60%, (see literature Organic Syntheses, Coll. Vol. 5, p.76 (1973); Vol. 45, p.7 (1965).) [0005] Its chemical reaction formula is as follows: [0006] [0007] 2) Cyclopentanone is produced by alkylation (benzylation) of enamine, and the total yield is less than 30%. The reaction formula is as follows: [0008] [0009] 3) Cyclopentanone is directly benzylated under the catalysis of sodium amide to obtain the product, with a total yield of less than 30%, (see lit...

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): C07C49/657C07C45/65
CPCC07C45/455C07C45/65C07C51/083C07C67/08C07C2601/08C07C49/657C07C49/792C07C69/738C07C59/84
Inventor 李德宝习文兵廖育能吴俊飞
Owner KUNSHAN RIKITA PHARMA
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