Highly regio- and chemoselective [2 + 2 + 2] cycloaddition of 1,6-heptadiynes with allenes catalyzed by cobalt complexesElectronic supplementary information (ESI) available: synthesis and characterization of compounds 4 and 6. See http://www.rsc.org/suppdata/cc/b2/b212260j/

Abstract

The CoI2(PPh3)2/Zn system effectively catalyzes the [2 + 2 + 2] ene-diyne cycloaddition of 1,6-heptadiynes with allenes in a highly regio- and chemoselective fashion to yield substituted benzene derivatives in good to excellent yields.