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:
Mar. 16, 1982
Filed:
Dec. 31, 1979
Applicant:
Inventors:
Steffen Piesch, Oberursel, DE;
Friedrich Engelhardt, Frankfurt am Main, DE;
Herbert Wille, Frankfurt am Main, DE;
Wolf Weidemuller, Frankfurt am Main, DE;
Artur Meyer, Schoneck, DE;
Assignee:
Cassella Aktiengesellschaft, Frankfurt, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
260317 ;
Abstract
The process for the preparation of a 3-(4-hydroxyanilino)carbazole of the formula ##STR1## wherein R is hydrogen, alkyl having 1 to 8 carbon atoms or halogenoalkyl having 1 to 8 carbon atoms, comprising reacting a 3-aminocarbazole of the formula ##STR2## with p-hydroquinone or p-aminophenol or a mixture of p-hydroquinone and p-aminophenol in at least stoichiometric amounts by heating to a temperature of 150.degree. to 300.degree. C. with exclusion of oxygen.