Preparation of aromatic hydroxycarboxylic acids

US4990660A · kind A · utility

Assignee

• BASF SE

Inventors

• Peter Neumann · Wiesloch, DE
• Ulrich Eichenauer · Frankfurt, DE

Key dates

• Filing date: Dec 21, 1988
• Grant date: Feb 5, 1991
• Expiry date: Dec 21, 2008

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C317/44
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Aromatic hydroxycarboxylic acids of the formula EQU (HO--).sub.n A--COOH where n is 1 or 2 and A is a radical from the benzene, naphthalene, biphenyl, diphenyl ether, diphenyl sulfide or diphenyl sulfone series, are prepared by a process in which an acylated aromatic compound of the formula EQU (R.sup.1 --CO--O--).sub.n A--CO--R.sup.2 where R.sup.1 and R.sup.2 independently of one another are each unsubstituted or substituted C.sub.1 -C.sub.4 -alkyl and n and A each have the abovementioned meanings, is oxidized with oxygen in the presence of a catalyst and of a solvent at from 20.degree. to 250.degree. C. to give a carboxylic acid of the formula EQU (R.sup.1 --CO--O--).sub.n A--COOH where R.sup.1, n and A have the abovementioned meanings, and the acyl group or groups is or are then eliminated.