Palladium-Catalyzed Esterification of Carboxylic Acids with Aryl Iodides.

The first palladium-catalyzed esterification of carboxylic acids with aryl iodides is described. A palladium-based catalytic system consisting of IBn (1,3-bis((pentafluorophenyl)methyl)imidazole-2-ylidene) ligand was found to significantly accelerate the aryl-O bond-forming esterification reaction. A series of aryl iodides and carboxylic acids undergoes a palladium-catalyzed coupling reaction to provide the corresponding aryl esters in moderate to good yields. In addition, sterically hindered aryl iodides and carboxylic acids were well-tolerated yielding the corresponding aryl esters.