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:
Sep. 15, 1998
Filed:
Sep. 13, 1994
Applicant:
Inventors:
Siegbert Rittner, Morfelden, DE;
Hans-Martin Ruffer, Hofheim, DE;
Jorg Schmid, Eppstein, DE;
Thomas Wisser, Limburg, DE;
Assignee:
Hoechst Aktiengesellschaft, Frankfurt, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
562406 ; 562467 ;
Abstract
A process for the preparation of 2-hydroxynaphthalene-6-carboxylic acid using potassium carbonate and CO at temperatures above 260.degree. C. and at a pressure of at least 10 bar comprises using 2-hydroxynaphthalene-3-carboxylic acid and/or 2-hydroxynaphthalene-3,6-dicarboxylic acid and/or their potassium salts and, if desired, potassium .beta.-naphtholate as starting materials. The process according to the invention enables a considerable increase, by reusing the secondary products, in the product selectivity with regard to 2-hydroxy-naphthalene-6-carboxylic acid.