title: Extended Bis(benzothia)quinodimethanes and Their Dications: From Singlet Diradicaloids to Isoelectronic Structures of Long Acenes.
abstract: Extended bis(benzothia)quinodimethanes and their dications were synthesized as stable species. The neutral compounds mainly have a quinoidal structure in the ground state but show increased diradical character with extension of the central quinodimethane unit. The dications exhibit similar electronic absorption spectra, NMR spectra, NICS values, and diatropic ring currents to their aromatic all-carbon acene analogues and thus can be regarded as genuine isoelectronic structures of pentacene, hexacene, and heptacene, respectively. Our research gave some insights into the design and synthesis of stable longer acene analogues.
authors.affiliation: Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore, Singapore.
authors.forename: Shaoqiang
authors.initials: S
authors.lastname: Dong
authors.affiliation: Department of Materials Science and Engineering, National University of Singapore, 119260, Singapore, Singapore.
authors.forename: Tun Seng
authors.initials: TS
authors.lastname: Herng
authors.affiliation: Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore, Singapore.
authors.forename: Tullimilli Y
authors.initials: TY
authors.lastname: Gopalakrishna
authors.affiliation: Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore, Singapore.
authors.forename: Hoa
authors.initials: H
authors.lastname: Phan
authors.affiliation: Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore, Singapore.
authors.forename: Zheng Long
authors.initials: ZL
authors.lastname: Lim
authors.affiliation: Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore, Singapore.
authors.forename: Pan
authors.initials: P
authors.lastname: Hu
authors.affiliation: Division of Chemistry & Biological Chemistry, School of Physical & Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore, Singapore.
authors.forename: Richard D
authors.initials: RD
authors.lastname: Webster
authors.affiliation: Department of Materials Science and Engineering, National University of Singapore, 119260, Singapore, Singapore.
authors.forename: Jun
authors.initials: J
authors.lastname: Ding
authors.affiliation: Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore, Singapore. chmcc@nus.edu.sg.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Chi
keywords: acenes; aromaticity; dications; diradicals; heteroacenes