Preparation of unsaturated diesters by catalytic oxidative carbonylation of diolefins

Abstract From the Canadian patent

A process for the preparation of an unsaturated diester having the formula, wherein R is an alkyl group of from 1 to 8 carbon atoms or an aralkyl group containing 6 carbon atoms in the ring and from 1 to 4 carbon atoms in the alkyl substituent and R1 to R4 is hydrogen, a halogen, an alkyl group of from 1 to 4 carbon atoms or an aryl group containing 6 carbon atoms in the ring, by reacting carbon monoxide and oxygen with a diolefin having the formula wherein R1 to R4 which may be the same or different is as hereinabove described in the presence of a catalytic amount of a platinum group metal compound a copper or, iron oxidant salt compound and a stoichiometric amount of a dehydrating agent. …