Title:
OPTICAL RESOLUTION OF (+,-)-CHROMANCARBOXYLIC ACID
Document Type and Number:
Japanese Patent JP3913329
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To carry out the optical resolution of (±)-6-hydroxy-2,5,7,8- tetramethylchroman-2-carboylic acid in high efficiency by using a specific resolution agent.
SOLUTION: For example, (±)-6-hydroxy-2,5,7,8-tetramethylchroman-2- carboxylic acid is mixed with an optically active N-benzyl-α-phenylethylamine and a solvent, dissolved by heating and cooled to attain a supersaturated state of the diastereomer salt. The supersaturated solution is inoculated with a small amount of preferably (+)-chromancarbonxylic acid.(-)-N-benzyl-α- phenylethylamine salt or (-)-chromancarboxylic acid.(+)-N-benzyl-α- phenylethylamine salt to effect the precipitation of the same kind of scarcely soluble diastereomer salt, which is separated by filtration, centrifugal separation, etc. The diastereomer salt is treated with a base to recover the resolution agent and then made to react with an acid to obtain (+)-chromancarboxylic acid or (-)-chromancarboxylic acid.
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Inventors:
Hiroyuki Nohira
Application Number:
JP24670197A
Publication Date:
May 09, 2007
Filing Date:
September 11, 1997
Export Citation:
Assignee:
KURARAY CO.,LTD.
International Classes:
C07D311/72; C07B57/00; (IPC1-7): C07D311/72; C07B57/00; //C07M7:00
Domestic Patent References:
| JP59144780A | ||||
| JP5255180A | ||||
| JP8169859A | ||||
| JP4198178A |