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The palladium-catalysed direct 2-, 4- or 5-arylation of a wide range of heteroaromatics with aryl halides proceed in moderate to good yields using the eco-friendly solvents carbonates. The best yields were obtained using benzoxazole or thiazole derivatives. The arylation of furan, thiophene, pyrrole, imidazole or isoxazole derivatives was found to require a more elevated reaction temperature. The direct arylation of heteroaromatics is an important field for research in organic synthesis due to the biological or physical properties of the aryl-heteroaryl derivatives.1 Ohta and co-workers reported in 1985–1992 that the direct 2- or 5-arylation of several heteroaromatics with aryl halides proceed inmoderate to good yields using Pd(PPh3)4 as the catalyst and DMAc as the solvent.2 Since these exciting results, the palladium-catalysed direct arylation of heteroaryl derivatives with aryl halides or triflates has proved to be a very powerful method for the synthesis of a wide variety of arylated heterocycles.3–10 Thi