Acenaphthenoannulation Induced by the Dual Lewis Acidity of Alumina

We have discovered a dual (i. e., soft and hard) Lewis acidity 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 through three-point annulation of the 1-(2-ethynyl-6-fluorophenyl)naphthalene moiety. The versatility of the developed method was demonstrated by the synthesis of unprecedented structural fragments of elusive geodesic graphene nanoribbons

An Indacenopicene‐based Buckybowl Catcher for Recognition of Fullerenes

A novel buckybowl catcher with an extended π-surface has been synthesized via cross-coupling of two bowl shaped bromoindacenopicene moieties with a tolyl linker. The obtained catcher has been unambiguously characterized by 2D-NMR and mass spectrometry. DFT calculations indicate that the curved shape of the receptor moieties is favourable for binding fullerenes. Effective binding was confirmed for interactions with C$_{60}$ and C$_{70}$ utilizing NMR spectroscopy and isothermal titration calorimetry (ITC). The resulting binding values show a higher affinity of the catcher towards C$_{70}$ over C$_{60}$. The designed catcher demonstrated the fundamental possibility of creating sensors for spherical aromaticity