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:
Nov. 24, 1987
Filed:
May. 02, 1984
Applicant:
Inventors:
Byron R Cotter, Northvale, NJ (US);
Henry C Lin, Grand Island, NY (US);
Joseph A Pawlak, Cheektowaga, NY (US);
Assignee:
Occidental Chemical Corporation, Niagara Falls, NY (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ; C07D / ;
U.S. Cl.
CPC ...
549246 ; 562507 ;
Abstract
4,4-dihalohexahydrophthalic anhydrides of the formula ##STR1## where Y is chlorine or fluorine, are prepared by the reaction of hydrogen fluoride with 4-chlorotetrahydrophthalic anhydride. The 4,4-dihalohexahydrophthalic anhydrides of this invention can be dehydrohalogenated by reaction with basic alumina to prepare a mixture of 4-fluorotetrahydrophthalic anhydride isomers of the formula ##STR2## The 4-fluorotetrahydrophthalic anhydrides can then be dehydrogenated by reaction with a dehydrogenation catalyst to prepare 4-fluorophthalic anhydride.