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. 07, 1989
Filed:
Jan. 29, 1987
Hans-Georg Brunner, Lausen, CH;
Urs Muller, Munchenstein, CH;
Ciba-Geigy Corporation, Ardsley, NY (US);
Abstract
The present invention relates to a novel, optimized process for the preparation of cyclohexanedionecarboxylic acid derivatives of formula I which can be carried out in a single vessel affording a very good yield, which process comprises heating a reactive carboxylic acid derivative of formula III ##STR1## wherein X is a halide, an alkylsulfonic or arylsulfonic acid radical or the molecular radical ##STR2## which is necessary to form an anhydride and R.sub.1 is alkyl or cycloalkyl, with an alkali metal cyanide or copper cyanide, in an inert organic solvent, to give a mixture, then adding in succession to said mixture, at a temperature in the range from 0.degree. C. to room temperature, zinc chloride, an equimolar amount, with respect to the carboxylic acid derivative of formula III, of a 3,5-cyclohexanedione-1-carboxylic acid derivative of formula II ##STR3## wherein A is an ester or amide radical, and, dropwise, an amine, and, after acidifying the reaction mixture with an aqueous acid, isolating the resultant 4-acyl-3,5-cyclohexanedione-1-carboxylic acid derivative of formula I ##STR4## by extraction. Said cyclohexanedionecarboxylic acid derivatives have herbicidal and plant growth regulating properties.