Treatment of various o-iodobenzaldehydes and o-iodophenyl ketones with alkynes in the presence of Co (dppe) I2 and Zn powder in acetonitrile at 80° C afforded the corresponding indenols in moderate to excellent yields with exceedingly high regioselectivity. For most unsymmetrical alkynes tested, the carbocyclization gave a single regioisomer.
