[n]Radialenes are alicyclic organic compounds containing n cross-conjugated exocyclic double bonds. An alicyclic compound is an Organic compound that is both Aliphatic and cyclic An organic compound is any member of a large class of Chemical compounds whose Molecules contain Carbon. Cross-conjugation is a special type of conjugation in a Molecule, when in a set of three Pi bonds only two pi-bonds interact with each other by conjugation An alicyclic compound is an Organic compound that is both Aliphatic and cyclic The double bonds are commonly alkene groups but those with a carbonyl (C=O) group are also called radialenes ^[1]. In Organic chemistry, an alkene, olefin, or olefine is an unsaturated Chemical compound containing at least one Carbon In Organic chemistry, a carbonyl group is a Functional group composed of a Carbon Atom double-bonded to an Oxygen For some members the unsubstituted parent radialenes are elusive but many substituted derivatives are known.

Radialenes are related to open-chain dendralenes and also to compounds like butadiene and benzene which also consist of a ring of sp² hydridized carbon atoms. Dendralenes are discrete Acyclic cross-conjugated Polyenes The simplest dendralene is Butadiene (1 or dendralene followed by Benzene, or benzol, is an organic Chemical compound and a known Carcinogen with the molecular formula C 6 H 6 -->In Chemistry

Radialenes are investigated in organic chemistry for their unusual properties and reactivity but have not ventured outside the laboratory. Organic chemistry is a discipline within Chemistry which involves the scientific study of the structure properties composition reactions, and preparation Reported uses are as experimental building blocks for novel organic conductors and ferromagnets ^[2]. The first radialene called hexaethylidencyclohexane was synthesised in 1961 ^[3].

Contents 1 Conformation 2 Synthesis & properties 2.1 [4]Radialene 3 References

Conformation

[3] and [4]radialenes are expected to have a planar molecular geometry with all carbon atoms in the same plane. Molecular geometry or molecular structure is the three- Dimensional arrangement of the Atoms that constitute a Molecule. This is verified experimentally in hexamethyl[3]radialene and cyclobutanetetraonetetrakis(hydrazone). Decamethyl[5]radialene has a twist envelope geometry with C₂ symmetry while a chair conformation is calculated for [6]radialene and found experimentally for hexa-(ethylidene)cyclohexane

Due to their specific pi-electron distributions, hydrocarbons such as perylene and triphenylene are not considered radialenes. Cyclohexane conformation is a much studied topic in Organic chemistry because of the complex interrelationship between the different conformers of Cyclohexane Perylene or perilene is a Polycyclic aromatic hydrocarbon with the Chemical formula 2012 occurring as a Brown Solid In Chemistry, the Organic compound triphenylene is a flat Polycyclic aromatic hydrocarbon (PAH consisting of four fused Benzene rings One study <name=Patra/> describes a [6]radialene composed of thiophene units ^[4]:

This compound is reported as planar with D_3h symmetry (X-ray diffraction) but not aromatic: the carbon-carbon bond lengths are unusually long (145 pm vs. Thiophene is the Heterocyclic compound with the formula C4H4S Molecular symmetry in Chemistry describes the Symmetry present in Molecules and the classification of molecules according to their symmetry X-ray scattering techniques are a family of non-destructive analytical techniques which reveal information about the crystallographic structure chemical composition A carbon-carbon bond is a Covalent bond between two Carbon Atoms. In Molecular geometry, bond length or bond distance is the average distance between nuclei of two bonded Atoms in a Molecule. A picometre ( American spelling: picometer, symbol pm) is a unit of Length in the Metric system, equal to one trillionth 140 pm for benzene) and the calculated NICS value is close to zero. Benzene, or benzol, is an organic Chemical compound and a known Carcinogen with the molecular formula C 6 H 6 If you are looking for the meteorological effect it is at Ring current.

Synthesis & properties

The parent [3],[4],[5] and [6]radialenes polymerize when in contact with oxygen.

[4]Radialene

The unsubstituted [4]radialene has been prepared in an elimination reaction of cis,trans,cis-tetra(bromomethyl)cyclobutane with sodium methoxide in ethanol ^[5]

Hydrogenation with platinum on carbon gives cis,cis,cis-tetramethylcyclobutane in accordance with the proposed structure. An elimination reaction is a type of Organic reaction in which two Substituents are removed from a molecule in either a one or two-step mechanism. Sodium methoxide is a chemical compound, with formula Na(CH3O Hydrogenation is the Chemical reaction that results in addition of Hydrogen (H2 Palladium on carbon, often referred to as Pd/C, is a form of Palladium used for Catalysis. On standing in air at room temperature the compound accepts oxygen and polymerizes. Room temperature (also referred to as ambient temperature) is a common term to denote a certain Temperature within enclosed space at which humans are accustomed In Polymer chemistry, polymerization is a process of reacting Monomer Molecules together in a Chemical reaction to form three-dimensional networks

References

The Journal of the American Chemical Society (usually abbreviated as J A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.

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