Zirconium triflate-catalyzed reactions of indole, 1-methylindole, and pyrrole with α,β-unsaturated ketone

The Zr(OTf)4-catalyzed reaction of indole, 1-methylindole or pyrrole with α,β-unsaturated ketone generated the corresponding trisindolyl-, tris(1-methylindolyl-), and trispyrrolylalkanes in moderate to high yields in the mixed solvent EtOH/H2O.