Practical copper-catalyzed N-arylation of nitrogen heterocycles with aryl halides under ligand and additive free conditions

N-arylation of a wide variety of nitrogen heterocycles with aryl iodides catalyzed by copper iodide under mild ligand and additive free conditions (nBu4NBr, PhMe, NaOH, reflux, 22 h) was accomplished in good to excellent yields (up to 95%) and substrate conversions (up to 99%).