Palladium catalyzed methoxycarbonylation of 1-dodecene in biphasic systems – Optimization of catalyst recycling

Abstract

The palladium catalyzed methoxycarbonylation of long-chain olefin 1‐dodecene in a liquid/liquid biphasic system composed of methanol as polar phase and the substrate/product as nonpolar phase is reported. The immobilization of the palladium based catalyst in the methanol phase is affected by the use of the watersoluble ligand SulfoXantPhos and methanesulfonic acid as co‐catalyst. We investigated these systems with respect to reaction performance and catalyst recycling by variation of the type and amount of co-solvent in both existing phases. By modifying these systems with a co-solvent, catalyst recycling could be improved compared to the benchmark system without co-solvents to a palladium and phosphorous leaching <1ppm. The applied homogeneously dissolved palladium catalyst could be quantitatively recycled four times via a simple phase separation without any loss in activity and selectivity.