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.