Controlled Monoarylation of Dibromoarenes in Water with a Polymeric Palladium Catalyst

A highly selective monoarylation of dibromoarenes was performed via the Suzuki-Miyaura cross-coupling with arylboronic acids with an amphiphilic polystyrene-poly(ethylene glycol) (PS-PEG) resin-supported phosphine-palladium complex in water ­under heterogeneous conditions to give bromobiaryls in high yields. Introduction of two different aryl groups on a aromatic moiety was achieved in a one-pot reaction by successive addition of two kinds of arylboronic acids under similar conditions. The polymeric ­palladium catalyst can be readily recovered and recycled.