Cuneane

Cuneane

Identifiers
CAS Number	20656-23-9
ChemSpider	124127
Jmol interactive 3D	Image
PubChem	140734 54749138 2R,4R,6R,8R 11194301 2S,4S,6S,8S
InChI InChI=1S/C8H8/c1-2-5(1)6-3-4(6)8(2)7(1)3/h1-8H Key: YIJMEXRVJPVGIY-UHFFFAOYSA-N
SMILES C12C3C4C3C5C1C2C45
Properties
Chemical formula	C8H8
Molar mass	104.15 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 (C₈H₈, Pentacyclo[3.3.0.0 ^2,4.0^3,7.0^6,8]octane) is a saturated hydrocarbon.^[1] Its name is derived from the Latin “cuneus”, meaning a wedge.^[2] Cuneane may be produced from cubane by metal-ion-catalyzed σ-bond rearrangement.^[3][4] Similar reactions are known for homocubane (C₉H₁₀) and bishomocubane (C₁₀H₁₀).^[5][6]

The cuneane molecule has three groups of equivalent carbon atoms (A, B, C), which have also been confirmed by NMR.^[7] 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.^[8][9]

Some cuneane derivatives have liquid crystal properties.^[10]

External links

• 2D and 3D Models of Dodecahedrane and Cuneane Assemblies Link

References

1. with 3D-structure (however molecular graph of cuneane is a planar graph)
2. R. Criegee, R. Askani (1968). "Octamethylsemibullvalene". Angewandte Chemie International Edition in English 7 (7): 537. doi:10.1002/anie.196805371.
3. Michael B. Smith, Jerry March (2001). March’s Advanced Organic Chemistry (5th ed.). John Wiley & Sons, Inc. p. 1459. ISBN 0-471-58589-0.
4. Philip E. Eaton, Luigi Cassar, Jack Halpern (1970). "Silver(I)- and palladium(II)-catalyzed isomerizations of cubane. Synthesis and characterization of cuneane". Journal of the American Chemical Society 92 (21): 6366–6368. doi:10.1021/ja00724a061.
5. Leo A. Paquette and John C. Stowell (1970). "Silver ion catalyzed rearrangements of strained .sigma. bonds. Application to the homocubyl and 1,1'-bishomocubyl systems". Journal of the American Chemical Society 92 (8): 2584–2586. doi:10.1021/ja00711a082.
6. W. G. Dauben, M. G. Buzzolini, C. H. Schallhorn, D. L. Whalen, K. J. Palmer (1970). "Thermal and silver ion catalyzed isomerization of the 1,1′-bishomocubane system: preparation of a new C₁₀H₁₀isomer". Tetrahedron Letters 11 (10): 787–790. doi:10.1016/S0040-4039(01)97830-X.
7. H. Guenther and W. Herrig (1973). "Anwendungen der ¹³C-Resonanz-Spektroskopie, X. ¹³C,¹³C-Kopplungskonstanten in Methylencycloalkanen". Chemische Berichte 106 (12): 3938–3950. doi:10.1002/cber.19731061217.
8. M.I. Trofimov, E.A. Smolenskii (2000). "Electronegativity of atoms of ring-containing molecules—NMR spectroscopy data correlations: a description within the framework of topological index approach". Russian Chemical Bulletin 49 (3): 402. doi:10.1007/BF02494766.
9. M.I. Trofimov, E.A. Smolenskii (2005). "Application of the electronegativity indices of organic molecules to tasks of chemical informatics". Russian Chemical Bulletin 54 (9): 2235. doi:10.1007/s11172-006-0105-6.
10. Bényei, Gyula; Jalsovszky, István; Demus, Dietrich; Prasad, Krishna; Rao, Shankar; Vajda, Anikó; Jákli, Antal; Fodor‐Csorba, Katalin (2006). "First liquid crystalline cuneane‐caged derivatives: a structure-property relationship study". Liquid Crystals 33 (6): 689–696. doi:10.1080/02678290600722940.