Theoretical studies of the structure and aromaticity of conjugation four-membered ring continuum with simple combination procedure of combining Kekule structures

Abstract

Because the number of pi electrons on the carbon rings is 4n, it can be classified cyclobutadiene into anti-aromatic compound. However, the aromaticity or anti-aromaticity for cyclobutadienoids series(butalene, bicyclobutadienylene, etc.) is unknown. In this conference, the geometries and the aromaticity for condensed cyclobutadienoid series are reported on the basis of ab initio MO theories. The stationary point structure of the series are also predicted by a simple selected combination of Kekule structures.