A mild and versatile method for palladium-catalyzed cross-coupling of aryl halides in water and surfactants

Various aqueous surfactants proved to be excellent media for carrying out palladium-catalyzed Suzuki-Miyaura cross-coupling reactions under mild conditions. The dehalogenation side reaction, which is usually a drawback with the aqueous protocol, was not observed. The concentration of the surfactant in water played a pivotal role for the reaction outcome. Smooth cross-coupling of iodoanisole and a variety of aryl bromides, including electron-rich derivatives, with aryl boronic acids occurred at room temperature in high yields either with [Pd(PPh3)(4)] or Pd/C as catalyst. The water-surfactant Pd/C system combines high activity under ambient conditions (air), easy separation and recyclability. Palladium acetate was found to be effective in cross-coupling of the less reactive aryl chlorides at 100 degreesC. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003).