Hydrocarbons dimerization

Chakarova SD, Schroder E (2005) van der Waals interactions of polycyclic aromatic hydrocarbon dimers, J. Chem. Phys, 122 054102... 

Sol. hydrocarbons, dimeric in CeHs. D2 affects exchange in ZrHj groups. 

The irradiation of aromatic compounds results in considerably lower yields of radiolysis products than does irradiation of aliphatic compounds of similar molecular weight and functional group composition. This has been attributed to effectiveness of the delocalized 7t-orbitals in accommodating excitation energy without permitting the molecule to dissociate. Nevertheless, some radiolysis does occur. Benzene is known to yield biphenyl, phenylcyclohexadiene, and a polymeric material of average composition (C6H7) which behaves as if it were an unsaturated hydrocarbon. Dimerization and polymer formation are also characteristic of the radiation... 

Finally, the thermolysis of 2,3-dimethylenebicyclo[2.2.0]hexane has been examined in an effort to determine the behavior of a 2,2 -bisallyl biradical forced to be nearly planar. The hydrocarbon dimerizes in a first-order reaction in modestly concentrated solution, and the presumed biradical can be trapped with 2,4-hexadiene with loss of stereochemistry of the diene.However, in the vapor phase at 110°C, first-order isomerization to a 2 1 mixture bicyclo[4.2.0]octa-1,5-diene (BOD), and 3,4-dimethylene-l,5-hexadiene (DMHD), occurs. ... 

Aromatic hydrocarbons dimerize in the presence of palladium(II) salts, at > 100°, with loss of hydrogens (van Helden and Verberg, 1965 lataaki and Yoshimoto, 1973). When appropriate oxidants are present in the reaction... 

To make the issue even more complex, two radicals can occasionally react with each other (dimerize) in a very exothermic formation of new hydrocarbons (dimers) that can reenter the reaction sequence and provide new species. For example, two propyl radicals might combine to form hexane (Fig. 11.8). Further pyrolysis of hexane would lead to many other products. 

Mackie ID, DiLabio GA (2(X)8) Interactions in large, polyaromatic hydrocarbon dimers application of density functional theory with dispersion corrections. J Phys Chem A 112 10968... 

The products of the reaction of radical anions, for example sodium naphthalene, with bromides and chlorides are the hydrocarbon, the olefin and alkylated dihydronaphthalene. Reaction with iodides gives hydrocarbon dimer in addition.The mechanism as shown is a result of numerous product and kinetic studies (2 4, 5). Two steps that merit further investigation are the... 

Form Supplied in commercially available as an approximately 1.7 M solution in pentane or heptane. Tetrameric in hydrocarbons, dimeric in diethyl ether, monomeric in THF although earlier reported as dimeric. In combination with tertiary polyamines such as N,N,N, N -tetramethyl-ethylenediamine (TMEDA), l,4-diazabicyclo[2.2.2]octane (DtYBCO), or N,N,N, N",N"-pentamethyldiethylenetriamine (PMDTA), reactivity is often increased. ... 

---