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:
Apr. 12, 1983
Filed:
May. 22, 1981
Applicant:
Inventors:
Hansjakob Fah, Ettingen, CH;
Alfred Grieder, Bockten, CH;
Assignee:
Ciba-Geigy Corporation, Ardsley, NY (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
546345 ;
Abstract
Production of 2,3,5-trichloropyridine by reacting 3,5-dichloro-2-pyridone at 30.degree. to 150.degree. with phosgene in the presence of an N,N-disubstituted formamide of the formula ##STR1## in which R.sub.1 and R.sub.2 can be identical or different and are each an alkyl group having 1 to 4 carbon atoms, or R.sub.1 and R.sub.2 together with the nitrogen atom form the pyrrolidino, piperidino or morpholino, and in the presence of an inert solvent. 2,3,5-Trichloropyridine is a valuable intermediate for producing herbicidally active .alpha.-[4-(3',5'-dichloropyrid-2-yloxy)-phenoxy]-alkanecarboxylic acids and derivatives thereof.