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:
Oct. 28, 1980
Filed:
Nov. 25, 1977
Applicant:
Inventors:
Siegfried Kintopf, Bensheim, DE;
Ulrich Kress, Bensheim, DE;
Assignee:
Ciba-Geigy Corporation, Ardsley, NY (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
548260 ; 548259 ;
Abstract
A process for the production of 2-aryl-2H-benzotriazoles comprises reducing and cyclizing the corresponding o-nitroazobenzenes with hydrogen at a temperature in the range of about 20.degree. C. to about 100.degree. C. and at a pressure in the range of about 15 psia (1 atmosphere) to about 1000 psia (66 atmospheres) in an organic solvent mixture containing an organic amine at a pH over 10 in the presence of noble metal hydrogenation catalyst, preferably palladium. High yields of pure product are obtained with a concomitant reduction of undesired by-products and a reduction in effluent pollution problems.