Hexaphenylbenzene

From Wikipedia, the free encyclopedia
Hexaphenylbenzene
IUPAC name

1,2,3,4,5,6-hexa(phenyl)benzene

Identifiers
CAS number 992-04-1 YesY
PubChem 70432
ChemSpider 63611 YesY
Jmol-3D images Image 1
Properties
Molecular formula C42H30
Molar mass 534.6876
Melting point 454-456 °C[2]
 YesY (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

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.[2]

Structure

Perspective view of the crystal structure of hexaphenylbenzene, showing the rotation of the phenyl rings. Hydrogen atoms have been omitted for clarity.[1]

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°,[1] while in the gas phase, they are perpendicular with some slight oscillations.[3]


References

  1. ↑ 1.0 1.1 Bart, J. C. J. (1968). "The crystal structure of a modification of hexaphenylbenzene". Acta Crystallographica, Section B: Structural Crystallography and Crystal Chemistry 24 (10): 1277. doi:10.1107/S0567740868004176. 
  2. ↑ 2.0 2.1 Louis Fieser (1973), "Hexaphenylbenzene", Org. Synth. ; Coll. Vol. 5: 604 
  3. ↑ Gust, D. (1977). "Restricted Rotation in Hexaarylbenzenes". J. Am. Chem. Soc. 99 (21): 6980–6982. doi:10.1021/ja00463a034. 
This article is issued from Wikipedia. The text is available under the Creative Commons Attribution/Share Alike; additional terms may apply for the media files.