R. Abbasoglu et al., THEORETICAL-STUDIES ON THE CONFIGURATIONS OF BENZHOMOBARRELENE DERIVATIVES, Turkish journal of chemistry, 22(3), 1998, pp. 201-207
Reaction of 7-carbomethoxy-cycloheptatriene with benzyne resulted in t
he formation of only one benzhomobarrelene isomer, 5A. Theoretically,
four addition products, 5A-D, can be formed from this reaction. Certai
n molecular mechanic calculations (MM2 force field) have been undertak
en on these isomers. It has been shown that the isomers 5A and 5C have
the lowest energies. The non-existence of 5C has been discussed in te
rms of a benzyne approach to a norcaradiene structure. Furthermore, MM
2 calculations on two different conformers of 5A have revealed that th
e bisected conformer 5AE has the highest strain energy. However, AM1 s
emiempirical calculations of those conformers have shown that the conf
ormer 5AE possesses a lower heat of formation than the isomer 5AA.