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:
Jun. 29, 1999
Filed:
Mar. 05, 1998
Thomas Schach, Gernsheim, DE;
Hans Schubert, Kelkheim, DE;
Clariant GmbH, Frankfurt, DE;
Abstract
A process for the preparation of N-carboxyalkyl-3-fluoro-4-dialkylaminoanilines, which comprises reacting, in a first step, 2-chloro-4,5-difluoronitrobenzene of the formula (I) ##STR1## with a secondary amine of the formula (II) HNR.sup.1 R.sup.2, in which R.sup.1 and R.sup.2, independently of one another, are identical or different and are an alkyl radical having from 1 to 10 carbon atoms or, together with the N atom to which they are bonded, form a ring having from 5 to 7 members, in the presence of a water-soluble amine which forms hydrofluorides and hydrochlorides which are liquid at the reaction temperature and work-up temperature or soluble in the reaction mixture, in the presence or absence of a solvent at -10 to 120.degree. C., reducing, in a second step, the reaction mixture containing the 2-chloro-4-dialkylamino-5-fluoronitrobenzene using hydrogen at from 30 to 150.degree. C. and from 1 to 350 bar in the presence of the water-soluble amine and in the presence of a noble-metal catalyst and, in a third step, reacting the reaction mixture containing the 3-fluoro-4-dialkylaminoaniline with a chloroformate of the formula (IV) ClCO.sub.2 R.sup.3, in which R.sup.3 is an alkyl radical having from 1 to 10 carbon atoms or an aralkyl radical having from 7 to 20 carbon atoms, at from 0 to 100.degree. C. in the presence of the water-soluble amine.