Synthesis, Physical Properties and Biradical Characters of Zethrene-based Polycylic Hydrocarbons

Abstract

Zethrene represents a class of polycyclic hydrocarbons (PHs) with a signature ?Z? shape, the structure of which can be viewed as either fusion of two phenalenyl moieties or dibenzoacenes. Expansion of the conjugation vertically or laterally will result in high order zethrenes (e.g. heptazethrene, octazethrene) or laterally extended zethrenes (e.g. dibenzozethrene, dibenzoheptazethrene), which exhibit prominent biradical contribution to the ground state due to the recovery of aromaticity in the biradical resonance form. For zethrene-based PHs, the physical properties are closely related to the structural significance and the biradical characters, and they are theoretically predicted to be good candidates as semiconductors, near-infrared dyes, non-linear optic and spintronic materials. The research of this thesis describes the several convenient synthetic approaches towards a series of stable and soluble zethrene, heptazethrene and dibenzoheptazethrene derivatives, the structure-property relationships are established for the better understanding of zethrene-based PHs and the practical applications in the future.