Activated Phenacenes from Phenylenes by Nickel‐Catalyzed Alkyne Cycloadditions

Going zigzag, helical, or in-between: Angular phenylenes show a propensity for adding alkynes from the bay region in processes catalyzed by [Ni(cod)(PMe3)2] (see scheme). These transformations generate novel strain- and electronically activated phenacenes. Mechanistic studies in conjunction with DFT calculations (R=Ph) provide a plausible mechanistic picture.