A Reusable Palladium(II)/Cationic 2,2′‐Bipyridyl Catalytic System for Hydroxycarbonylation of Aryl Iodides in Water

A water‐soluble palladium(II)/cationic 2,2′‐bipyridyl system was utilized to catalyze hydroxycarbonylation of aryl iodides in the presence of a pressurized CO atmosphere under a basic aqueous solution at 100 °C. The residual aqueous solution could be reused in several times with only a slight decrease in catalytic activity. Thus, it reduced wastage of the precious metal in the reaction. A variety of aromatic carboxylic acids could still be obtained in high yields with the catalytic amount to 0.01 mol%.