Synthesis of isoflavones by room-temperature nickel-catalyzed cross-couplings of 3-iodo(bromo)chromones with arylzincs

new concise, facile method for synthesis of isoflavones was accomplished in moderate to good yields for 3-iodochromones or 3-bromochromones and arylzinc bromides via Negishi cross-coupling reaction catalyzed by NiCl_2/PPh_3 or NiCl_2(PPh_3)_2 at room temperature. The Isoflavone core was synthesized in four steps in good yield, starting from commercially available 2-hydroxyacetophenone and aromatic bromide. Three steps of the procedure were carried out at room temperature.