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. 14, 1998
Filed:
May. 02, 1996
Ralf Pfirmann, Griesheim, DE;
Hans Schubert, Kelkheim, DE;
Hoechst Aktiengesellschaft, , DE;
Abstract
The present invention relates to a process for the preparation of compounds of the formula ##STR1## in which the radicals R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are identical or different and are COOH, H, F, Cl, Br, CF.sub.3, OH, an alkoxy or alkyl radical having in each case 1 to 4 carbon atoms or a radical --NR.sup.6 R.sup.7, in which R.sup.6 and R.sup.7 are identical or different and are H, an alkyl radical having 1 to 4 carbon atoms or a phenyl radical, by dissolving in water a compound of the formula ##STR2## in which the radicals R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are identical or different and have the abovementioned meaning or, in departure therefrom, instead of H can be COOH, admixing the aqueous solution with a water-insoluble amine which is inert under the reaction conditions and carrying out the decarboxylation at a pH of 3 to 9 and a temperature of 70.degree. to 210.degree. C. in the presence or absence of a water-insoluble solvent which is inert under the reaction conditions and in the presence or absence of a decarboxylation catalyst.