Manufacture of butanedicarboxylic acid esters

US4169956A · kind A · utility

Assignee

• BASF SE

Inventors

• Rudolf Kummer · Bischofswerda, DE
• Heinz-Walter Schneider · Ludwigshafen, DE
• Franz-Josef Weiss · Schifferstadt, DE

Key dates

• Filing date: Sep 8, 1978
• Grant date: Oct 2, 1979
• Expiry date: Sep 8, 1998

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C67/38
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for the manufacture of butanedicarboxylic acid esters, wherein PA1 (a) an aqueous cobalt salt solution is treated with carbon monoxide and hydrogen in the presence of active charcoal, PA1 (b) the resulting aqueous solution is extracted with butadiene or with a hydrocarbon mixture containing butadiene, PA1 (c) the butadiene, or butadiene/hydrocarbon mixture, containing cobalt carbonyl hydride, cobalt carbonyl and butenyl-cobalt tricarbonyl, is reacted with carbon monoxide and an excess of an alkanol of 1 to 4 carbon atoms in the presence of a tertiary nitrogen base, PA1 (d) the tertiary nitrogen bases contained in the resulting reaction mixture are removed from the latter to the extent of leaving from 0.1 to 0.3 mole per mole of pentenoic acid ester, excess hydrocarbons are also removed, the pentenoic acid ester remaining in the reaction mixture is reacted with carbon monoxide and an alkanol of 1 to 4 carbon atoms, and thereafter excess alkanol and free nitrogen base are distilled off and PA1 (e) the residual reaction mixture, containing cobalt catalysts, butanedicarboxylic acids and by-products is treated with an oxidizing agent in an aqueous acid medium and the mixture i…