The first general method for the palladium-catalyzed Suzuki−Miyaura and carbonyl enolate coupling of unactivated aryl arenesulfonates was developed utilizing XPhos and Pd(OAc)2. This is of significant interest because aryl tosylates and aryl benzenesulfonates are more easily handled and considerably less expensive than aryl triflates. This catalyst system effects the coupling of a variety of aryl, heteroaryl, and extremely hindered arylboronic acids with different aryl tosylates, under mild conditions. The same catalyst was employed in the first carbonyl enolate coupling of aryl arensulfonates.
“The First General Palladium Catalyst for the Suzuki−Miyaura and Carbonyl Enolate Coupling of Aryl Arenesulfonates”, J. Am. Chem. Soc., 2003, 125(39), 11818-11819.