Cu(acac)2-Catalyzed N-Arylations of Phenylurea with Aryl Boronic Acid

Abstract Cu(acac)2 activates aryl boronic acids for the reaction with NH2-phenylurea without additional ligand and heating. The procedure is simple, general, ligand-free, milder than the palladium-catalyzed arylation, and avoids the use of toxic phosphine ligands.