Octalene

Octalene is a hypothetical organic chemical compound consisting of eight benzene rings fused together in a circular fashion. It is a polycyclic aromatic hydrocarbon (PAH) and, as such, is predicted to have interesting electronic and optical properties. Octalene has not yet been synthesized or definitively characterized, making its properties largely theoretical.

The anticipated structure of octalene suggests significant ring strain due to the forced planarity and bond angles differing from ideal sp2 hybridization. This strain is expected to influence its stability and reactivity. Furthermore, the large conjugated system of octalene is predicted to result in a relatively small HOMO-LUMO gap, suggesting that it might be a strong chromophore and potentially useful in organic electronics.

Due to the challenges involved in synthesizing such a strained and potentially unstable molecule, research efforts have primarily focused on theoretical studies to predict its properties and explore potential synthetic routes. These studies have considered various aspects, including its electronic structure, vibrational modes, and thermodynamic stability. While octalene itself remains elusive, related macrocyclic structures with fewer fused benzene rings have been synthesized, providing insight into the synthesis and properties of this class of compounds.