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S-o-chloromandelic acid preparation method

A technology of o-chloromandelic acid and hydrochloric acid is applied in the preparation of carboxylates, the preparation of organic compounds, organic chemical methods, etc., can solve problems such as failure to see, and achieves high splitting efficiency, good product purity, and simple operation. Effect

Inactive Publication Date: 2015-12-23
彭静
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the report on how to prepare S-o-chloromandelic acid cannot be seen.

Method used

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Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0012] (1) Resolution of o-chloromandelic acid

[0013] In a 50L reactor, add 15L methanol and 15L water to prepare the solvent required for the reaction. Then add 1.87KG racemic o-chloromandelic acid in the kettle, start stirring and heat up. Under the condition of reflux, 2.00KG of S-1-naphthylethylamine was added dropwise to the system. After the dropwise addition was completed, react under reflux conditions for 1.5 hours, then cool down to room temperature, and filter the precipitated white solid to obtain 1.58KG of the crude product S-1-naphthylethylamine salt of S-o-chloromandelic acid. Add the obtained 1.58KGS-S-1-naphthylethylamine salt of o-chloromandelic acid into 15L of methanol solution, heat up to dissolve, wait for the solid to completely dissolve, then cool down, and after cooling down to room temperature, filter the crystalline solid , 1.46KG of S-1-naphthylethylamine salt of refined S-o-chloromandelic acid was obtained.

[0014] (2) Acid hydrolysis of salt ...

Embodiment 2

[0019] (1) Resolution of o-chloromandelic acid

[0020] In a 50L reactor, add 10L ethanol and 20L water to prepare the solvent required for the reaction. Then add 1.87KG racemic o-chloromandelic acid in the kettle, start stirring and heat up. Under the condition of reflux, 2.0KG of S-1-naphthylethylamine was added dropwise to the system. After the dropwise addition was completed, react under reflux conditions for 1 hour, cool down to room temperature, and filter the precipitated white solid to obtain 1.49KG of crude S-1-naphthylethylamine salt of S-o-chloromandelic acid. Add the obtained 1.56KGS-S-1-naphthylethylamine salt of o-chloromandelic acid into 15L of ethanol solution, heat up to dissolve, wait for the solid to completely dissolve, then cool down, and after cooling down to room temperature, filter the crystalline solid , S-1-naphthylethylamine salt 1.38KG of refined S-o-chloromandelic acid was obtained.

[0021] (4) Acid hydrolysis of salt to obtain S-o-chloromandel...

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PUM

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Abstract

The present invention discloses a method for preparing S-o-chloromandelic acid by using S-1-naphthyl ethylamine as a chiral splitting agent. The method comprises: adding o-chloromandelic acid to an alcohol solvent as a raw material, adding a splitting agent S-1-naphthyl ethylamine at a certain temperature in a dropwise manner, carrying out a reflux reaction, cooling, crystallizing, carrying out suction filtration to obtain a S-1-naphthyl ethylamine salt of the S-o-chloromandelic acid, re-crystallizing the salt, acidifying, extracting, drying, and concentrating to obtain the S-o-chloromandelic acid, wherein the solution containing the splitting agent is merged, and alkalization, extraction, drying, concentration and other operations are performed to recover the splitting agent S-1-naphthyl ethylamine. According to the present invention, the preparation method has characteristics of mild condition, simple operation, good product yield, high product optical purity, splitting agent recycling and the like, and is suitable for the industrial production of the S-o-chloromandelic acid.

Description

technical field [0001] The invention relates to a method for preparing chiral compounds by chemical resolution, in particular to a method for preparing S-o-chloromandelic acid by using S-1-naphthylethylamine as a resolving agent. Background technique [0002] O-chloromandelic acid has two enantiomeric configurations of R-type and S-type, and is widely used in many fields such as pharmaceutical production, asymmetric synthesis, and optical resolution. But the current research is basically about how to prepare R-o-chloromandelic acid. However, the report on how to prepare S-o-chloromandelic acid cannot be seen. So how to prepare S-o-chloromandelic acid becomes the problem to be solved by the present invention. Contents of the invention [0003] The present invention uses S-1-naphthylethylamine as a resolving agent, and can successfully realize the resolution and preparation of S-o-chloromandelic acid. The invention operates as follows: [0004] The present invention uses...

Claims

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Application Information

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IPC IPC(8): C07C59/56C07C51/487C07B57/00
CPCC07C51/487C07B57/00C07B2200/07C07C59/56
Inventor 彭静
Owner 彭静