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. 25, 1990
Filed:
Feb. 28, 1989
Applicant:
Inventors:
Alexander Moller, Gelnhausen, DE;
Heinz Friedrich, Hanau, DE;
Herbert Kuhn, Alzenau, DE;
Kurt Winkler, Rossbach, DE;
Assignee:
Degussa Aktiengesellschaft, Frankfurt am Main, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ; C07D / ;
U.S. Cl.
CPC ...
546319 ; 546318 ;
Abstract
The invention is directed to a method of producing coarse-crystalline nicotinic acid with a high degree of purity in which 3-cyanopyridine is saponified with aqueous alkali hydroxide and the nicotinic acid is allowed to crystallize out of the alkali nicotinate solution obtained in this manner under the addition of mineral acid at temperatures between 99.degree. and 135.degree. C. The pH is kept above 3.7.