Process for the preparation of 4-hydroxy-quinoline-3-carboxylic acids

US4804760A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Michael Schriewer · Odenthal, DE
• Klaus Grohe · Odenthal, DE

Key dates

• Filing date: Apr 28, 1987
• Grant date: Feb 14, 1989
• Expiry date: Apr 28, 2007

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C205/61
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for the preparation of a compound of the formula ##STR1## in which Y is a nitrile group, an ester group COOR.sup.1 or an acid amide CONR.sup.2 R.sup.3, PA0 R.sup.1, R.sup.2 and R.sup.3 each independently is hydrogen or C.sub.1 -C.sub.4 -alkyl, and R.sup.3 may also be phenyl, and PA0 X.sup.2, X.sup.3, X.sup.4 and X.sup.5 each independently is hydrogen, halogen, nitro, cyano, alkyl having 1-3 carbon atoms, alkoxy having 1-3 carbon atoms, alkylmercapto having 1-3 carbon atoms, alkyl-sulphonyl having 1-3 carbon atoms, or a phenylsulphonyl group which is optionally substituted in the aryl radical, comprising reacting an aminoacrylate of the formula in which PA0 X.sup.1 is halogen, a nitro group, an alkoxy, alkoxy, alkylmercapto or alkylsulphonyl group having 1-3 carbon atoms in each case, or an arylsulphonyl group, W is hydrogen or a --CH.sub.2 CH.sub.2 Z radical, Z is a nitrile group, an ester group COOR.sup.4 or an acid amide group CONR.sup.5 R.sup.6, and R.sup.4, R.sup.5 and R.sup.6 each independently is hydrogen or C.sub.1 -C.sub.4 -alkyl, and R.sup.5 may also be phenyl, with an acid acceptor in an aprotic solvent. Some of the reactants are new, as are the products which a…