The hitherto unisolated, thermodynamically unstable C(2)-symmetric conformer of hexabenzotriphenylene (1) has been efficiently synthesized by palladium-catalyzed cyclotrimerization of 9, 10-didehydrophenanthrene (4). The barriers to conformational interconversion of 1 are examined experimentally and by computational studies.

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A nanographene formed by the fusion of 22 benzene rings has been prepared by combining an in-solution Pd-catalyzed cycloaddition reaction and on-surface Au-promoted cyclodehydrogenation. The structure and electronic properties of the resulting three-fold symmetric C66H24 molecule have been characterized by scanning probe microscopy with atomic resolution and corroborated by theoretical modelling.

The use of BINAP-based palladium(0) catalysts in the reaction of 7-methoxy-1,2-didehydronaphthalene (2) and dimethyl acetylenedicarboxylate (DMAD) affords non-racemic 9,12-dimethoxypentahelicene 1 with reasonable ees, among other cycloaddition products. This is the first example of an enantioselective, metal-catalyzed cycloaddition involving arynes.

A game of dominos: Domino [4+2]/[4+2] cycloadditions between 1,8‐difurylnaphthalene and arynes provide the corresponding adducts in a highly diastereoselective manner. This new synthetic methodology enables the preparation of elusive perylene derivatives with a remarkable reduced HOMO–LUMO gap, a crucial feature for organic semiconductors.