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. 03, 1993
Filed:
Nov. 16, 1982
Applicant:
Inventors:
Lawrence B Fertel, Williamsville, NY (US);
William S Derwin, Buffalo, NY (US);
Assignee:
Occidental Chemical Corporation, Niagara Falls, NY (US);
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
562451 ; 564177 ; 564179 ; 562474 ;
Abstract
Disclosed is a method of making 3-hydroxy-2,4,5-trifluorobenzoic acid. A aqueous solution is prepared of an alkali metal base and a tetrafluorophthalimide. The solution is heated to produce a mixture of a salt of a 4-hydroxy-3,5,6-trifluorophthalamic acid and a salt of a 3-hydroxy-2,4,5-trifluorobenzamide. The solution is neutralized with acid to form a precipitate of the 4-hydroxy-3,5,6-trifluorophthalamic acid and the 3-hydroxy-2,4,5-trifluorobenzamide. The precipitate is reacted with a mineral acid to produce 3-hydroxy-2,4,5-trifluorobenzoic acid.