title: Fluoreno[4,3-c]fluorene: a closed-shell, fully conjugated hydrocarbon.
abstract: The synthesis and optoelectronic properties of 24 π-electron, formally antiaromatic 4,11-di-t-butyl-1,8-dimesitylfluoreno[4,3-c]fluorene (FF) are presented. The solid-state structure shows that the outer rings are aromatic, while the central four rings possess a bond-localized 2,6-naphthoquinone dimethide motif (in red). The biradical character of FF is assessed experimentally and computationally; the results of which implicate a closed-shell ground state.
authors.affiliation: Department of Chemistry and Materials Science Institute, University of Oregon, Eugene, Oregon 97403-1253, United States.
authors.forename: Bradley D
authors.initials: BD
authors.lastname: Rose
authors.forename: Chris L
authors.initials: CL
authors.lastname: Vonnegut
authors.forename: Lev N
authors.initials: LN
authors.lastname: Zakharov
authors.forename: Michael M
authors.initials: MM
authors.lastname: Haley