Abstract:
The π-conjugation, aromaticity, and stability of the
newly synthesized 12-infinitene and of other infinitenes comprising
8-, 10-, 14-, and 16-arene rings are investigated using density
functional theory. The π-electron delocalization and aromatic
character rooted in infinitenes are quantified in terms of molecular
electrostatic potential (MESP) topology. Structurally, the infinitene
bears a close resemblance of its helically twisted structure to
the infinity symbol. The MESP topology shows that infinitene
possesses an infinity-shaped delocalization of the electron density
that streams over the fused benzenoid rings. The parameter
i=1 i
3 , derived from the eigenvalues (λi) corresponding to the MESP minima, is used for quantifying the aromatic character of
arene rings of infinitene. The structure, stability, and MESP topology features of 8-, 10-, 12-, 14-, and 16-infinitenes are also
compared with the corresponding isomeric circulenes and carbon nanobelts. Further, the strain in all such systems is evaluated by
considering the respective isomeric planar benzenoid hydrocarbons as reference systems. The 12-infinitene turns out to be the most
aromatic and the least strained among all the systems examined.
