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:
Sep. 10, 1991
Filed:
Aug. 22, 1990
Hartmut Heise, Bad Soden am Taunus, DE;
Manfred Hintzmann, Hofheim am Taunus, DE;
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
A process for the preparation of 4-acylamino-2-aminoalkoxybenzenes of the general formula (1) ##STR1## in which R denotes an alkyl-C.sub.1 -C.sub.6 - or alkoxy-C.sub.1 -C.sub.4 -alkylene-C.sub.1 -C.sub.4 group and R' denotes a methyl or ethyl group, by pumping a solution or suspension of a 2,4-dinitroalkoxybenzene of the general formula (2) ##STR2## in which R has the abovementioned meaning, in a butyl acetate into a stirred suspension of a nickel catalyst on a kieselguhr carrier in butyl acetate, which has been initially introduced into an autoclave, at a hydrogen pressure of about 5 to about 50 bar, and a temperature of about 60.degree. to about 120.degree. C., at a rate which corresponds to the rate of hydrogenation of 2,4-dinitroalkoxybenzene to 2,4-diaminoalkoxybenzene, dehydrating the reduction solution by azeotropic distillation, after the hydrogenation, and acylating the resulting 2,4-diaminoalkoxybenzene with about 0.90 to 0.99 mole of the anhydride of an alkylmonocarboxylic acid having 2 to 3 carbon atoms, relative to 1 mole of 2,4-diaminoalkoxybenzene, at about -5.degree. to about +15.degree. C.