Circulene

A circulene is a macrocyclic arene in which a central n-sided polygon is completely surrounded and fused by benzenoids. [5]circulene (corannulene), [6]circulene (coronene), [7]circulene, and [12]circulene (kekulene) have all been synthesized in the laboratory. These compounds belong to a larger class of geodesic polyarenes. Whereas [5]circulene is bowl-shaped and [6]circulene is planar, [7]circulene has a unique saddle-shaped structure (compare to cones and partial cones in calixarenes). Conceptually related compounds are the helicenes.

The isolation of quadrannulene or tetrabenzo[4]circulene has been reported.

The isolation of the [8]circulene derivative 2,5,6,9,10,13,14-octamethyl-3,4,7,8,11,12,15,16-octa(4-tolyl)[8]circulene has been reported Tetrabenzo[8]circulene (TB8C), a functionally stable form of the parent molecule [8]circulene has also been reported.

Hetrocyclic circulene is a macrocyclic arene in which a central n-sided polygon is completely surrounded and fused by heterocycle. Sulflower is a stable heterocyclic octacirculene based on thiophene.

Corannulene ([5]circulene)

Coronene ([6]circulene)

[7]circulene

Sulflower, an octacirculene

Kekulene ([12]circulene)

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