
A polyquinane
polycyclic compound
In the field of organic chemistry, a polycyclic compound is an organic compound featuring several closed rings of atoms, primarily carbon. These ring substructures include cycloalkanes, aromatics, and other ring types. They come in sizes of ...
consisting of fused five-membered
hydrocarbon
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic, and their odors are usually weak or ...
rings. If the compound is
unsaturated instead of saturated, it is called a polyquinene. The simplest polyquinane is the
bicyclic
In chemistry, a bicyclic molecule () is a molecule that features two joined rings. Bicyclic structures occur widely, for example in many biologically important molecules like α-thujene and camphor. A bicyclic compound can be carbocyclic (a ...
compound bicyclo
.3.0ctane. Other members are triquinacene and
dodecahedrane
Dodecahedrane is a chemical compound, a hydrocarbon with formula , whose carbon atoms are arranged as the vertices (corners) of a regular dodecahedron. Each carbon is bound to three neighbouring carbon atoms and to a hydrogen atom. This compound ...
.
Triquinacene
The compound triquinacene, sometimes simply called quinacene (tricyclo
4,10">.2.1.04,10eca-2,5,8-triene) is the second member of a family of polyquinenes. It was synthesized in 1964 in the group of
R. B. Woodward
Robert Burns Woodward (April 10, 1917 – July 8, 1979) was an American organic chemist. He is considered by many to be the most preeminent synthetic organic chemist of the twentieth century, having made many key contributions to the subject, ...
in connection with its suspected
homoaromatic properties—though it was found to have no such properties—and also as part of a failed attempt to synthesize the then-elusive compound dodecahedrane. Triquinacene is stable, and has a
melting point
The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depends ...
of 18 °C. The final step of its synthesis is a double
Cope reaction
The Cope reaction or Cope elimination, developed by Arthur C. Cope, is an elimination reaction of the N-oxide to form an alkene and a hydroxylamine.
Mechanism and applications
The reaction mechanism involves an intramolecular 5-membered cyclic tr ...
to form two of the three
alkene
In organic chemistry, an alkene is a hydrocarbon containing a carbon–carbon double bond.
Alkene is often used as synonym of olefin, that is, any hydrocarbon containing one or more double bonds.H. Stephen Stoker (2015): General, Organic, an ...
s.
:
See also
* Fused 6 aromatic membered rings: the
acene
In organic chemistry, the acenes or polyacenes are a class of organic compounds and polycyclic aromatic hydrocarbons made up of benzene () rings which have been linearly fused. They follow the general molecular formula .
The larger represent ...
s
* Triquinacene is isomeric with:
bullvalene
Bullvalene is a hydrocarbon with the chemical formula . The molecule has a cage-like structure formed by the fusion of one cyclopropane and three cyclohepta-1,4-diene rings. Bullvalene is unusual as an organic molecule due to the and bonds fo ...
,
diisopropenyldiacetylene
References
{{reflist
Polycyclic nonaromatic hydrocarbons
Cyclopentanes