The valence isomeric equilibria between cycloheptatriene and norcaradiene and, as well, their substituted derivatives at position 7 containing strong electron withdrawing groups (7-cyano, 7,7-dicyano and 7,7-difluoro substituted) were investigated computationally using ab initio methods and charge density topological analysis at the 6-31G*, 6-31G** and MP2/6-31G** levels of theory. The calculated relevant cross sections of the potential energy surface shows that the 7,7-dicyanonorcaradiene, in which the CN group acts as a σ- and π-acceptor, behaves as a stable neutral homoaromatic compound. As a comparison, the destabilized 7,7-difluoronorcaradiene, in which fluorine substituents act as a σ-acceptor and a π-donor, was studied also.
ASJC Scopus subject areas
- Condensed Matter Physics
- Physical and Theoretical Chemistry