PALLADIUM-CATALYZED CARBONYLATION OF IODOARENES IN AQUEOUS SOLUBILIZED SYSTEMS

Iodobenzene and substituted iodobenzenes can be easily carbonylated into benzoic acids under mild conditions, with simple palladium salts as catalysts and normal pressure of CO, by using aqueous microemulsions of the oil-in-water kind as the reaction media. Surfactants of all three kinds, anionic, nonionic, and cationic, and simple aliphatic alcohols can be used to form the microemulsion media for carbonylation. The use of nonionic surfactants, the derivatives of polyethyleneglycol, is the most advantageous method as the surfactant is highly efficient in small amounts without a cosurfactant because of its strong solubilizing ability.