Preparation of adipic acid

US4931590A · kind A · utility

Assignee

• BASF SE

Inventors

• Rudolf Kummer · Bischofswerda, DE
• Franz Merger · Bischofswerda, DE
• Werner Bertleff · Viernheim, DE
• Rolf Fischer · Heidelberg, DE

Key dates

• Filing date: Jun 10, 1988
• Grant date: Jun 5, 1990
• Expiry date: Jun 10, 2008

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C67/39
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Adipic acid is prepared by a process which comprises the following steps: PA1 (a) Hydroformylation of a pentenoic ester by reaction with carbon monoxide and hydrogen at elevated temperatures and under superatmospheric pressure in the presence of a cobalt carbonyl or rhodium carbonyl complex with formation of a mixture of 5-, 4- and 3-formylvaleric esters, PA1 (b) isolation of the 5-formylvaleric ester from the resulting mixture of 5-, 4- and 3-formylvaleric esters, a mixture essentially consisting of 4- and 3-formylvaleric esters remaining, PA1 (c) dehydrocarbonylation of the mixture consisting essentially of 4- and 3-formylvaleric esters in the presence of one or more elements of subgroup 8 of the Periodic Table at from 50.degree. to 400.degree. C. with formation of pentenoic esters, and recycling of the latter to stage (a) for hydroformylation, PA1 (d) oxidation of the 5-formylvaleric ester from stage (b) with molecular oxygen or a gas containing molecular oxygen to give a monoester of adipic acid, and PA1 (e) hydrolysis of the monoester of adipic acid to give adipic acid.