title: Synthetic procedure for various selenium-containing electron donors of the bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) type.
abstract: Six selenium variants of BEDT-TTF have been successfully synthesized by a newly developed synthetic method that involves a combination of two key reactions for the construction of two kinds of heterocyclic rings: the first is a one-pot formation of 1,3-dichalcogenole-2-chalcogenones from a common starting material, THP-protected 2-(ethynylthio)ethanol, leading to the inner five-membered rings, and the other is the annelation of the outer six-membered heterocyclic ring onto the inner ring by an intramolecular transalkylation reaction on a chalcogen atom. This method turned out to be widely applicable to the syntheses of the electron donors of bis(ethylenedithio)- and bis(ethyleneselenothio)-substituted types. However, synthetic attempts to form analogous donors of the bis(ethylenediseleno)-substituted type from THP-protected 2-(ethynylseleno)ethanol were unsuccessful. This is attributable to the predominance of side-reactions via a seleniranium (episelenonium) salt over the desired six-membered ring formation by transalkylation via a seleninium salt.
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan. ktakimi@hiroshima-u.ac.jp
authors.forename: Kazuo
authors.initials: K
authors.lastname: Takimiya
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Jigami
authors.forename: Minoru
authors.initials: M
authors.lastname: Kawashima
authors.forename: Mie
authors.initials: M
authors.lastname: Kodani
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Aso
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Otsubo