64418-33-3

Upstream product

• 623-26-7 terephthalonitrile 
• 67-56-1 methanol 
• 92-52-4 biphenyl 
• 508-32-7 1,7,7-trimethyltricyclo[2.2.1.02,6]heptane 

Relevant academic research and scientific papers

The photochemical nucleophile-olefin combination, aromatic substitution (photo-NOCAS) reaction. Part 5: methanol-monoterpenes (α- and β-pinene, tricyclene, and nopol), 1,4-dicyanobenzene

The reactivity of the radical cations of α- and β-pinene (8 and 9), tricyclene (18), and nopol (23) has been studied.The radical ions were generated, in acetonitrile-methanol (3:1), by single electron transfer (set) to the singlet excited state of 1,4-dicyanobenzene (1).Biphenyl (3) was used as a codonor.The cyclobutane rings of the initially formed radical cations of α- and β-pinene (8 cation radical and 9 cation radical) cleave to distonic radical cations that react as tertiary alkyl cations and allylic radicals.The results of ab initio molecular orbital calculations (STO-3G) are consistent with the observation that the positive charge is largely associated with the tertiary alkyl moiety while the spin density is largely distributed over the allylic radical.There was no evidence, experimental or theoretical, indicative of a bonding interaction between the cationic and allylic moieties of these distonic radical cations.The cyclobutane ring cleavage is irreversible.The radical cation of tricyclene (18) also gives 1:1:1 (nucleophile:cyclopropyl:aromatic) adducts.The regio- and stereochemistry of the adducts, and the nucleophile selectivity, are all indicative of nucleophile-assisted cleavage of the radical cation (18 cation radical).The radical cation of nopol (23 cation radical) also cleaves to the distonic radical cation.The cyclobutane ring cleavage must be rapid; intramolecular 1,5-endo cyclization of the hydroxyl group cannot compete.

Cleavage of radical cations of alkenes; 1-butene and 4,4-dimethyl-1-pentene. Ab initio calculations on the interaction between the allyl and alkyl radical and carbocation moieties

Carbon-carbon bond cleavage of the radical cations of 1-butene (C4H8+*) and 4,4-dimethyl-1-pentene (C7H14+*) will generate the allyl and alkyl radical and carbocation fragments.Alternative bonding rearrangements between the allyl and methyl moieties in C4H8+* and between the allyl and tert-butyl moieties in C7H14+*, possible metastable intermediates or transition states preceding complete separation of the fragments, have been investigated by ab initio molecular orbital calculations.Structures were fully optimized at the UHF/6-31G* or UHF/STO-3G levels, and some ofthe calculations on C4H8+* were expanded with single point MP2/6-31G*//UHF/6-31G* computations.The C4H8+* radical cation, having a structure similar to that of 1-butene, is more stable than the separated fragments: 183 kJ mol-1 lower in energy than the sum of the energies of the allyl cation and the methyl radical, and 385 kJ mol-1 lower than the sum of the energies of an allyl radical and a methyl cation, at the MP2/6-31G* level.The corresponding values at the UHF/STO-3G level are 276 and 415 kJ mol-1, respectively.There is less bonding interaction between the allyl and tert-butyl moieties in C7H14+*.The summation of the energies of the allyl radical and the tert-butyl cation is 123 kJ mol-1 lower than the summation of the energies of the allyl cation and the tert-butyl radical, and 115 kJ mol-1 higher in energy than the bonded radical cation C7H14+*, at the UHF/STO-3G level.These calculated values are compared with thermochemical data and with experimetal results on the cleavage of these, and related, radical cations. Key words: radical cation, cleavage, ab initio calculations, electron transfer, photochemistry.