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:
Jun. 27, 1978
Filed:
May. 04, 1976
Applicant:
Inventor:
Freimund Rohrscheid, Kelkheim, Taunus, DT;
Assignee:
Hoechst Aktiengesellschaft, Frankfurt am Main, DT;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ; C07C / ;
U.S. Cl.
CPC ...
2603452 ; 2605 / ;
Abstract
Naphthalene-1,4,5,8-tetracarboxylic acid and typical derivative(s) thereof is (are) prepared by oxidation of periacenaphthindenones of the formula ##STR1## where R is H or lower alkyl, in a lower aliphatic carboxylic acid with nitric acid, optionally using also oxygen, in the presence of oxidation catalysts at temperatures above about 100.degree. C; the reaction product being worked up in known manner. Naphthalene-1,4,5,8-tetracarboxylic acid is an important preliminary product for the manufacture of dyestuffs.