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.