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:
May. 04, 1993
Filed:
Mar. 30, 1992
Applicant:
Inventors:
B Franklin Gupton, Virginia Beach, VA (US);
John Saukaitis, East Greenwich, RI (US);
Assignee:
Hoechst Celanese Corporation, Somerville, NJ (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
546116 ; 546321 ; 203 72 ;
Abstract
In one embodiment this invention provides a process for converting a pyridine-2,3-dicarboxylic acid diester to the corresponding cyclic anhydride directly, without any recovery and purification of the pyridine-2,3-dicarboxylic acid intermediate. An important aspect of the invention process is the utility of pure pyridine-2,3-dicarboxylic acid diester starting matter. A procedure for providing pure diester starting material is demonstrated.