A palladium-phosphine catalytic system as an active and recycable precatalyst for Suzuki coupling in water

The Suzuki-Miyaura reaction of various aryl halides with aryl boronic acids using {[Ph2PCH2PPh2CH=C(O)(C10H7)]PdCl2} as a catalyst has been investigated. The X-ray crystal structure of the catalyst reveals a five-membered chelate ring formed by coordination of the ligand through the phosphine group and the ylidic carbon atom to the metal center. This palladacycle exhibited excellent activities and reusability in the aqueous phase for the Suzuki cross-coupling reactions of arylboronic acids with aryl halides. The proposed protocol featured mild reaction conditions and notable simplicity and efficiency using Cs2CO3 as a base in water. The catalytic system could be reused four times without significant loss of activity.