Furan‐Extended Helical Rylenes with Fjord Edge Topology and Tunable Optoelectronic Properties

Abstract

AbstractLateral furan‐expansion of polycyclic aromatics, which enables multipleO‐doping and peripheral edge evolution of rylenes, is developed for the first time. TetrafuranylperyleneTPF‐4CNand octafuranylquaterryleneOFQ‐8CNwere prepared as model compounds bearing unique fjord edge topology and helical conformations. Compared toTPF‐4CN, the higher congenerOFQ‐8CNdisplays a largely red‐shifted (≈333 nm) and intensified absorption band (λmax=829 nm) as well as a narrowed electrochemical band gap (≈1.08 eV) due to its pronounced π‐delocalization and emerging of open‐shell diradicaloid upon the increase of fjord edge length. Moreover, strong circular dichroism signals in a broad range until 900 nm are observed for open‐shell chiralOFQ‐8CN, owing to the excellent conformational stability of its central bis(tetraoxa[5]helicene) fragments. Our studies provide insights into the relationships between edge topologies and (chir)optoelectronic properties for this novel type ofO‐doped PAHs.