Cyclization method of 4-substituted-2-oxazolidone

A technology of oxazolidinone and chiral amino alcohol, which is applied in organic chemistry and other fields, can solve problems such as safety hazards, and achieve the effect of reducing safety hazards and reducing production costs

Active Publication Date: 2014-01-29
NANTONG WANNIANCHANG PHARMA
View PDF5 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Thereby, existing method has the problem of potential...

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0017] Preparation of s-(+)-4-benzyl-2-oxazolidinone

[0018] Add 750kg of toluene, 130kg of potassium carbonate, and 151kg of L-phenylalaninol into the 20001 reactor, add 120kg of ethyl chloroformate dropwise at 60-80°C, and keep warm for 1 hour after the dropwise addition to obtain the acyl compound of chiral amino alcohol. compounds. Lower the temperature to below 40°C and put in 2kg of polyethylene glycol 400 (PEG-400), heat and reflux to separate water for 1-2 hours. After completion of the reaction, cool down to 70-80°C, add 450kg of water, keep standing at 60-70°C for stratification, re-extract the water layer with 200kg of toluene, and combine the organic solution layers. After the organic layer is concentrated, it is transferred to a crystallization kettle, cooled to 10-15°C, discharged and centrifuged, and the product is vacuum-dried. The output is 167kg, the yield is 95%, the content is more than 99.5%, and the ee value is more than 99.5%.

Embodiment 2

[0020] Preparation of (S)-4-phenyl-2-oxazolidinone

[0021] Add 750kg of toluene, 130kg of potassium carbonate, and 137kg of L-phenylalaninol into the 20001 reactor, add 120kg of ethyl chloroformate dropwise at 60-80°C, and keep warm for 1 hour after the dropwise addition to obtain the acyl compound of chiral amino alcohol. compounds. Lower the temperature to below 40°C and put in 2kg of polyethylene glycol 400 (PEG-400), heat and reflux to separate water for 1-2 hours. After the reaction is complete, cool down to 70-80°C and add 450kg of water, keep standing at 60-70°C for stratification, re-extract the water layer with 200kg of toluene, and combine the organic solution layers. After the organic layer was concentrated, it was transferred to a crystallization kettle, and the temperature was lowered to 10-15° C., which was discharged and centrifuged, and the product was vacuum-dried. The yield was 154 kg, and the yield was 95%. The content is above 99.5%, and the ee value is ...

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 cyclization method of 4-substituted-2-oxazolidone. The method is implemented through the following steps: (1) acylation: acylating chiral alkamine in a toluene solvent by adopting chloro-formate in the presence of potassium carbonate, so as to obtain chiral alkamine acylate; (2) cyclization: carrying out cyclization reaction through taking PEG-400 as a phase transfer catalyst, thereby obtaining 4-substituted-2-oxazolidone. Compared with the prior art, the cyclization method disclosed by the invention has the advantages that the adopted phase transfer catalyst is low in cost and is free of risk, reacting steps are reduced, the cost is reduced, and the conditions are mild, so that the method is suitable for industrial production.

Description

technical field [0001] The invention relates to a cyclization method of 4-substituted-2-oxazolidinone, which belongs to the technical field of synthesis of heterocyclic compounds. Background technique [0002] 4-substituted-2-oxazolidinone belongs to chiral auxiliary agent, which is a new technology of asymmetric synthesis, all of which are enantiomeric compounds. These compounds are temporarily connected to the substrate through covalent bonds. During the reaction process, these chiral auxiliary agents induce desired chirality, and finally these chiral auxiliary agents are broken and recovered. [0003] Such 4-substituted-2-oxazolidinone compounds are generally formed from chiral amino acids as starting materials through four steps of esterification, reduction, acylation and cyclization. Potassium tert-butoxide with high price and high risk should be used in the cyclization reaction. Therefore, the existing method has the problem of potential safety hazards in industriali...

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): C07D263/24
CPCC07D263/22
Inventor 许陈兵顾理群鲍烨华蔡发明
Owner NANTONG WANNIANCHANG 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