The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 27, 1983
Filed:
Oct. 20, 1981
Applicant:
Inventors:
Assignee:
Sumitomo Chemical Company, Limited, Osaka, JP;
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
2604 / ;
Abstract
A method for preparing an optically active carboxylic acid ester of the formula (I): ##STR1## wherein X is a hydrogen atom or a fluorine atom, and * indicates an asymmetric carbon atom, which is an A.alpha.-isomer having an (S)-configuration on both the acid and alcohol moieties, or rich in said A.alpha.-isomer, which method comprises crystallizing said A.alpha.-isomer from a solution of an A-isomer of the formula (I) having an (S)-configuration on the acid moiety in the presence of a crystal that is of substantially pure A.alpha.-isomer and in the presence or absence of a basic catalyst.