Superphenalene

Superphenalene is a very large polycyclic aromatic hydrocarbon (PAH) with chemical formula C96H30. It can be formally considered to consist of three fused superbenzenes (hexa-peri-hexabenzocoronene).

It can be considered as an overlapping structure of three hexa-peri-hexabenzocoronenes arranged symmetrically around a center. These have also been known as building blocks of molecular electronics since 2004 as they form self-assembling columns and nanotubes.

It and its hexa-tert-butyl derivative were first prepared in 1997, along with a collection of other very large PAHs. Due to the low solubility of these compounds, they could only be characterized by mass spectrometry when they were first synthesized, as neither NMR nor UV-Vis data could be collected.

Occurrence
It is not known to occur naturally.

Properties
Superphenalene has a planar geometry. With 540,000 mesomeric boundary structures, it has significantly more than hexabenzocoronene (250), supernaphthalene (16,100) and also buckminsterfullerene (12,500). The molecule has a threefold symmetry axis perpendicular to the molecule (C3).