Process for the preparation of monocarboxylic anhydrides

US4952727A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Gerhard Luft · Mühltal, DE
• Peter Trabold · Darmstadt, DE

Key dates

• Filing date: May 3, 1989
• Grant date: Aug 28, 1990
• Expiry date: May 3, 2009

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01J2531/822
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

In the process for the preparation of monocarboxylic anhydrides of the general formula (RCO).sub.2 O by reacting a carboxylic acid ester of dialkyl ether of the general formula RCOOR or ROR, where R in each case denotes the same alkyl radical having 1 to 4 carbon atoms, with carbon monoxide in the gas phase in the presence of iodine or bromine or compounds thereof as reaction promoter, and in the presence of a supported catalyst, at temperatures of from 130.degree. to 400.degree. C. and pressures of from 1 to 150 bar, where, in the supported catalyst, an organosilicon compound is bonded, as a polyfunctional coupling agent, on the one hand to a support material and on the other hand to a noble-metal compound from group VIII of the Periodic Table, a chelate-forming organosilicon compound of the general formula ##STR1## is employed as the polyfunctional coupling agent, where X=Cl, Br or --OR.sup.2 ; PA0 Y=-NR.sub.2.sup.4, a nitrogen-containing aryl radical, --PR.sub.2.sup.4, AsR.sub.2.sup.4, --SR.sup.4 or --SH; PA0 Z=zero, arylene or phenylene (optionally ortho-, meta-or para-substituted), PA0 R.sup.1 =C.sub.1 to C.sub.5 -alkyl; PA0 R.sup.2 =C.sub.1 to C.sub.5 -alkyl or --C.sub.6 H.su…