A Synthetic Strategy for the Construction of Functionalized Triphenylene Frameworks via Palladium Catalyzed Intramolecular Annulation/Decyanogenative C–H Bond Alkenylation

The palladium catalyzed synthesis of 14-phenylbenzo­[f]­tetraphene-9-carbonitrile derivatives as core polycyclic aromatic hydrocarbons (PAHs) was achieved via an intramolecular annulation and decyanogenative C–H bond alkenylation strategy. A readily synthesized Knoevenagel condensation product of [1,1′-biphenyl]-2,2′-dicarbaldehyde with benzyl cyanide converted successfully into 14-phenylbenzo­[f]­tetraphene-9-carbonitrile derivatives in excellent yields up to 94%. The transformation involves an intramolecular cascade C–C bond formation along with a C–H bond cleavage sequence.