First application of homogeneous Pd nanoparticles prepared by pulsed laser ablation in liquid to a Suzuki-type reaction

Palladium nanoparticles are a valuable alternative to molecular catalysts for not requiring costly and toxic ligands. In this study palladium nanoparticles were produced by either pulsed laser ablation in liquid or direct reactions between ascorbic acid and a palladium salt. The obtained nanoparticles have been characterized by TEM, XRD and XPS techniques and they have been applied to the catalysis of the ligand-free Suzuki-type cross-coupling reaction. Methyl (E)-4-bromocrotonate has been coupled to different aryl and heteroarylboronic acids with yield up to 81% and selectivity between 85 and 90%. Investigations on catalytic reusability of the NPs have shown that they could be used for three or ten catalytic cycles without loss of activity, respectively for LAL or chemically synthesized Pd NPs.