Hexaphenylbenzene is an aromatic compound composed of a benzene ring substituted with six phenyl rings.
It may be prepared through a Diels-Alder reaction by refluxing tetraphenylcyclopentadienone and diphenylacetylene in benzophenone or other high-temperature solvent.
Due to steric congestion among the phenyl rings, the stable conformation of this molecule has the phenyl rings rotated out of the plane of the central benzene ring. In the crystalline form shown on the left, the molecule forms a propeller-like conformation in which the phenyl rings are rotated about 65°, while in the gas phase, they are perpendicular with some slight oscillations.
Compounds belonging to the wider class of hexaarylbenzenes are of some scientific interest