Process for the production of carboxylic acid anhydrides.

摘要

A process for the production of a carboxylic acid anhydride comprises contacting a reaction composition comprising a carboxylic acid ester, a hydrocarbyl halide and/or a hydrocarbyl ether reactant and a hydrocarbyl halide promoter with carbon monoxide in the presence of a catalyst comprising an insoluble polymer support having pendant quaternised N-base or alkylated N-oxide pyridine groups supporting a rhodium species in which process the rhodium species is prevented from leaching from the polymer support by maintaining throughout the process a finite concentration of carboxylic acid anhydride in the reaction composition.