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:
Aug. 18, 1998
Filed:
Dec. 26, 1996
Applicant:
Inventors:
Assignee:
Sumitomo Chemical Company Limited, Osaka, JP;
Primary Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
544 94 ;
Abstract
A process for producing isatoic anhydrides of the formula (II): ##STR1## which comprises reacting an anthranilic acid of formula (I): ##STR2## or a salt thereof with phosgene using a mixed solvent of water and an organic solvent miscible with water and inert to the reaction; conducting the reaction in the coexistence of an alkylpyridinium salt in an aqueous solvent; or using a mixed solvent of water and a specific amount of an organic solvent substantially immiscible with water and inert to the reaction.