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:
Feb. 21, 2006
Filed:
Sep. 28, 2001
Applicants:
Hans Rupert Merkle, Ludwigshafen, DE;
Erich Fretschner, Neckarsteinach, DE;
Inventors:
Hans Rupert Merkle, Ludwigshafen, DE;
Erich Fretschner, Neckarsteinach, DE;
Assignee:
BASF Aktiengesellschaft, Ludwigshafen, DE;
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07D 231/16 (2006.01); C07D 231/18 (2006.01);
U.S. Cl.
CPC ...
Abstract
The present invention relates to a process for preparing 1-substituted 5-chloro-4-methylpyrazoles of the general formula Iwith the meaning for R stated in claim, in which a 4-methylpyrazole of the formula IIis reacted with chlorine, the resulting mixture of monochlorinated and dichlorinated product is fractionated by distillation, and subsequently the dichlorinated compound is dehalogenated to compound II and returned to the reaction with chlorine.