Cuneane

Cuneane

Ball and stick model of cuneane (1R,2R,3S,4S,5S,6R,7R,8S) Ball and stick model of cuneane (1R,2R,3S,4S,5S,6R,7R,8S)
Names
Preferred IUPAC name Pentacyclo[3.3.0.02,4.03,7.06,8]octane
Identifiers
CAS Number	20656-23-9 checkY
3D model (JSmol)	Interactive image
ChemSpider	124127 checkY
ECHA InfoCard
E number
PubChem CID	140734
CompTox Dashboard (EPA)	{{#property:P3117}}
InChI InChI=1S/C8H8/c1-2-5(1)6-3-4(6)8(2)7(1)3/h1-8H checkY Key: YIJMEXRVJPVGIY-UHFFFAOYSA-N checkY
SMILES C12C3C4C3C5C1C2C45
Properties
Chemical formula	C8H8
Molar mass	104.152 g·mol−1
Density	1.578 g/ml
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Cuneane (from Latin cuneus 'wedge') is a saturated hydrocarbon with the formula C₈H₈ and a 3D structure resembling a wedge, hence the name. Cuneane may be produced from cubane by metal-ion-catalyzed σ-bond rearrangement. Similar reactions are known for homocubane (C₉H₁₀) and bishomocubane (C₁₀H₁₂).

File:CubaneToCun.png

Synthesis of cuneane from cubane

Molecular geometry

The carbon atoms in the cuneane molecule form a hexahedron with point group C_2v. The cuneane molecule has three kinds of equivalent carbon atoms (A, B, C), which have also been confirmed by NMR. The molecular graph of the carbon skeleton of cuneane is a regular graph with non-equivalent groups of vertices, and so it is a very important test object for different algorithms of mathematical chemistry.

File:Cuneane 2D.svg

Equivalent carbon atoms in cuneane

Derivatives

Some cuneane derivatives have liquid crystal properties.