title: Synthesis of dibenzochalcogenaborins and systematic comparisons of their optical properties by changing a bridging chalcogen atom.
abstract: Novel hetero-pi-conjugated compounds (dibenzochalcogenaborins) with the same molecular framework, bearing a boron atom as an acceptor and chalcogen atoms as a donor, were synthesized, and systematic comparisons among these molecules were performed. X-ray crystallographic analysis of these molecules showed similar structures with high planarity. UV/Vis spectroscopy and theoretical calculations revealed that the absorption maxima and the HOMO-LUMO gap changed by systematically changing the bridging chalcogen atom. Dibenzooxaborin and dibenzothiaborin showed fluorescence emission both in solution and in the solid state with a small Stokes shift, indicating the high rigidity of these compounds. On the other hand, dibenzoselenaborin exhibited a very weak fluorescence as a result of the heavy atom effect.
authors.affiliation: Department of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Junji
authors.initials: J
authors.lastname: Kobayashi
authors.forename: Keiko
authors.initials: K
authors.lastname: Kato
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Agou
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kawashima