Diradical B/N‐Doped Polycyclic Hydrocarbons

Abstract

AbstractHeterocyclic diradicaloids with atom‐precise control over open‐shell nature are promising materials for organic electronics and spintronics. Herein, we disclose quinoidal π‐extension of a B/N‐heterocycle for generating B/N‐type organic diradicaloids. Two quinoidal π‐extended B/N‐doped polycyclic hydrocarbons that feature fusion of the B/N‐heterocycle motif with the antiaromatics‐indacene or dicyclopenta[b,g]naphthalene core were synthesized. This quinoidal π‐extension and B/N‐heterocycle leads to their open‐shell electronic nature, which stands in contrast to the multiple‐resonance effect of conventional B/N‐type emitters. These B/N‐type diradicaloids have modulated (anti)aromaticity and enhanced diradical characters comparing with the all‐carbon analogues, as well as intriguing properties, such as magnetic activities, narrow energy gaps and highly red‐shifted absorptions. This study thus opens the new space for both of B/N‐doped polycyclic π‐systems and heterocyclic diradicaloids.