A Simple Route to Novel Palladium(II) Catalysts with Oxazolin-2-ylidene Ligands

Novel palladium(II) complexes with oxazolin-2-ylidene ligands have been synthesized via
direct reaction of palladium acetate and oxazolium salts, prepared in turn by alkylation of
oxazole with methyl iodide or benzylic bromides. The resulting complexes have been
characterized and used as catalysts in Heck coupling reactions of aryl bromides, where they
exhibit remarkable catalytic activity, higher than that of the closely related bis-imidazolin-2-ylidene and bis-benzothiazolin-2-ylidene complexes.