Dicationic Heteroacenes Containing Thio- or Selenopyrylium Moieties

Article abstract of DOI:10.1021/acs.organomet.9b00100

Dicationic heteroacenes that bear thio- or selenopyrylium moieties were synthesized by addition reactions of the corresponding diones with a Grignard reagent, followed by a dehydration reaction of the resulting diols with Br?nsted acid. Alternatively, these dicationic heteroacenes were obtained from two-electron oxidations of the corresponding sulfur- or selenium-containing quinoids. The electronic structures of these dicationic heteroacenes were examined by NMR and UV-vis-NIR spectroscopy in conjunction with density functional theory calculations. The results of this combined experimental and theoretical approach strongly imply effective conjugation of 22π-electrons in a system that is distributed over the entire pentacene framework.