We have discovered a dual (i. e., soft and hard) Lewisacidity of alumina that enables rapid one-pot π-extension through the activation of terminal alkynes followed by C-F activation. The tandem reaction introduces an acenaphthene fragment - an essential moiety of geodesic polyarenes. This reaction provides quick access to elusive non-alternant polyarenes such as π-extended buckybowls and helicenes
The title structure suggested for the higher-melting product of catalytic cyclodehydrogenation of 1–2′-biphenylyl-3,4-dihydronaphthalene has been confirmed by an unambiguous synthesis.