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

Resolution preparation method of S-4-methoxymandelic acid

A technology of methoxymandelic acid and S-4-, which is applied in the field of separation and preparation of S-4-methoxymandelic acid, can solve the problems of difficult to obtain, low optical purity, biological resolution catalyst and chemical resolution agent Expensive and other issues, to achieve the effect of simple operation, high optical purity, and mild conditions

Inactive Publication Date: 2015-11-25
彭静
View PDF8 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The two reported methods have the disadvantages of low optical purity of the product, expensive bioresolution catalysts and chemical resolution agents, and difficulty in obtaining them.

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

[0007] (1) Resolution of 4-methoxymandelic acid

[0008] In a 1000ML round bottom flask, add 400ML methanol as a solvent, 18.2G racemic 4-methoxymandelic acid, start stirring, and heat up. Under the condition of reflux, 18.0G of S-1-naphthylethylamine was added dropwise to the system. After the dropwise addition was completed, react under reflux conditions for 1.5 hours, lower to 0°C, and filter the precipitated white solid to obtain 13.5 g of crude S-1-naphthylethylamine salt of S-4-methoxymandelic acid. Add the obtained S-1-naphthylethylamine salt of 13.5GS-4-methoxymandelic acid into 140ML of methanol solution, heat up to dissolve, and wait for the solid to completely dissolve, then cool down to 0°C, and The crystalline solid was filtered to obtain 12.4 g of refined S-1-naphthylethylamine salt of S-4-methoxymandelic acid.

[0009] (2) Acid hydrolysis of salt to obtain S-4-methoxymandelic acid

[0010] Dissolve 12.4G of S-1-naphthylethylamine salt of S-4-methoxymandelic a...

Embodiment 2

[0014] (1) Resolution of 4-methoxymandelic acid

[0015] In a 1000ML round bottom flask, add 300ML ethanol as a solvent, 18.2KG racemic 4-methoxymandelic acid, start stirring, and heat up. Under the condition of reflux, 20.0G of S-1-naphthylethylamine was added dropwise to the system. After the dropwise addition was completed, react under reflux conditions for 1.5 hours, lower to 0°C, and filter the precipitated white solid to obtain 14.3 g of crude S-1-naphthylethylamine salt of S-4-methoxymandelic acid. Add the S-1-naphthylethylamine salt of the obtained 14.3GS-4-methoxymandelic acid into 150ML ethanol solution, heat up to dissolve, and wait for the solid to completely dissolve, then cool down to 0°C, and The crystalline solid was filtered to obtain 13.1 G of refined S-1-naphthylethylamine salt of S-4-methoxymandelic acid.

[0016] (2) Acid hydrolysis of salt to obtain S-4-methoxymandelic acid

[0017] Dissolve 13.1G of S-1-naphthylethylamine salt of S-4-methoxymandelic a...

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 resolution preparation method of S-4-methoxymandelic acid. The method comprises steps as follows: 4-methoxymandelic acid after racemization reacts with a resolving agent (S)-(-)-1-(1-naphthyl)ethylamine in an alcohol solvent, and on the basis of difference of solubility of generated salt with two configurations including R and S in the alcohol solvent after the reaction, (S)-(-)-1-(1-naphthyl)ethylamine salt of S-4-methoxymandelic acid is obtained through crystallization and separation; S-4-methoxymandelic acid is obtained after the salt is recrystallized, acidized, extracted with an organic solvent and concentrated; a reacted and recrystallized mother solution after alcohol removal through evaporation is mixed with another solution containing (S)-(-)-1-(1-naphthyl)ethylamine, and (S)-(-)-1-(1-naphthyl)ethylamine can be recycled after the mixed solution is alkalinized, extracted with an organic solvent and concentrated. The resolution preparation method of S-4-methoxymandelic acid has the advantages that conditions are mild, the operation is simple, the product yield and the optical purity are high, the resolving agent can be recycled and the like, and the method is very suitable for preparing and producing S-4-methoxymandelic acid.

Description

technical field [0001] The invention relates to a method for splitting and preparing chiral α-hydroxy carboxylic acid, in particular to a method for splitting and preparing S-4-methoxymandelic acid. Background technique [0002] 4-Methoxymandelic acid, as a chiral α-hydroxy carboxylic acid, has two enantiomeric configurations of R-type and S-type, and has important applications in many fields such as pharmaceutical production and asymmetric synthesis. In current reports, the methods for preparing S-4-methoxymandelic acid can be divided into asymmetric hydrolysis and chemical resolution. Asymmetry is hydrolysis. D-4-methoxymandelic acid methyl ester is used as raw material to obtain S-4-methoxymandelic acid through enzyme-catalyzed asymmetric hydrolysis (Journal of the Chemical Society, p.2069-2072), The chemical resolution method is to use (2S,3S)-2,3-dibenzyloxy-1,4-bis(hydroxylamine)butane as a resolving agent to split 4-methoxymandelic acid to obtain S - 4-Methoxymandel...

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): C07C59/64C07C51/487C07C51/42
CPCC07C51/487C07B57/00C07B2200/07C07C51/42C07C59/64
Inventor 彭静
Owner 彭静