Microwave Energized Synthesis of 2-Aroylindole Derivatives: Piperidine/DMF as an Effective Medium

A convenient and efficient protocol has been developed for the synthesis of 2-aroylindoles (3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, 3j) in good yields by the reaction of 2-aminoketones (1a, 1b, 1c) with phenacyl bromides (2a, 2b, 2c, 2d). The reaction success varied with different bases and solvents in both conventional and microwave methods. But finally, it was established that piperidine in DMF was an effective medium to carry out the reaction under microwave irradiation conditions.