Process for the preparation of monocarboxylic anhydrides

US4959498A · kind A · utility

Inventors

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

Key dates

• Filing date: Mar 17, 1989
• Grant date: Sep 25, 1990
• Expiry date: Mar 17, 2009

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C51/56
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The process for the preparation of monocarboxylic anhydrides of the general formula (RCO).sub.2 O is carried out by reacting a carboxylic ester or a dialkyl ether of the general formula RCOOR or ROR, in which 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 a supported catalyst. The reaction takes place by means of bromine or iodine or compounds thereof as reaction promoter. The support material in the catalyst supports a noble metal chelate compound which is formed by a noble metal compound from group VIII of the periodic table and a chelating agent containing organonitrogen, organophosphorus, organoarsenic, organosulfur or mercapto groups and substituted in its basic structure with alkyl, aryl or aralkyl groups. The reaction is carried out at temperatures from 130.degree. to 400.degree. C. and pressures from 1 to 150 bar.