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:
Jun. 08, 1993
Filed:
Dec. 17, 1991
Applicant:
Inventors:
Tamio Shirafuji, Ehime, JP;
Kiyomi Sakai, Ehime, JP;
Kensen Okusako, Ehime, JP;
Yoshitaka Nishida, Ehime, JP;
Assignee:
Sumitomo Chemical Co., Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
549290 ;
Abstract
A process for producing 3,4-dihydrocoumarin comprising cyclization and dehydrogenation of a 3-(2-cyclohexanoyl)propionic acid ester, in which a reaction mixture obtained by the cyclization and dehydrogenation is washed with an alkali to reduce the dihydrocinnamic acid content of the reaction mixture to 1% by weight or less and/or previously distilling the reaction mixture to remove high-boiling substances, and then subjected to rectification to recover 3,4-dihydrocoumarin. The thus obtained 3,4-dihydrocoumarin has high purity and high quality sufficient for use as a perfume as it is.