A mild and efficient protocol for the phosphine-free Suzuki-Miyaura coupling reaction of aryl bromides with arylboronic acids has been developed which utilizes the commercially available 10% Pd/C (3.5 mol% Pd) in ethanol-water (1:1) and Na2CO3 at room temperature. The reaction is convenient, environmentally benign and generates excellent yields of the coupled products (94-100%). The catalyst can be recycled using simple filtration and washing sequences without significant decrease in the yield of coupling product up to the fourth run.
Suzuki-Miyaura coupling - palladium - catalysis - heterogeneous