title: The facile generation of a tetramethyleneethane type radical cation and biradical utilizing a 3,4-di(alpha-styryl)furan and a photoinduced ET and back ET sequence.
abstract: Product analyses and nanosecond time-resolved spectroscopy on laser flash photolysis were studied for the photoinduced electron-transfer reaction of 3,4-di(alpha-styryl)furan (6a). A combination of these results, kinetic, density functional theoretical (DFT), and time-dependent DFT analyses enabled assignment of the absorption to the tetramethyleneethane (TME)-type radical cation (7a*+, lambda(max) = 392 nm) and the corresponding singlet biradical ((1)7a**, lambda(max) = 661 nm). These two intermediates were mechanistically linked to each other with a facile back electron-transfer reaction. The present studies provide a new method for the generation of aryl-substituted TME-type intermediates.
authors.affiliation: Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan.
authors.forename: Teruyo
authors.initials: T
authors.lastname: Ikeda
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ikeda
authors.forename: Yasutake
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Masafumi
authors.initials: M
authors.lastname: Yamada
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Mizuno
authors.forename: Shozo
authors.initials: S
authors.lastname: Tero-Kubota
authors.forename: Seigo
authors.initials: S
authors.lastname: Yamauchi
mesh_terms: D000475:Alkenes / Q000737:chemistry* / Q000528:radiation effects; D002412:Cations / Q000737:chemistry / Q000528:radiation effects; D004583:Electrons; D004980:Ethane / Q000031:analogs & derivatives* / Q000737:chemistry / Q000528:radiation effects; D005609:Free Radicals / Q000737:chemistry / Q000528:radiation effects; D005663:Furans / Q000737:chemistry* / Q000528:radiation effects; D007834:Lasers; D009682:Magnetic Resonance Spectroscopy / Q000379:methods / Q000592:standards; D008956:Models, Chemical; D015394:Molecular Structure; D010777:Photochemistry; D010782:Photolysis; D011789:Quantum Theory; D012015:Reference Standards
chemical_list: C527957:3,4-di(alpha-styryl)furan; D000475:Alkenes; D002412:Cations; D005609:Free Radicals; D005663:Furans; C527958:tetramethyleneethane; D004980:Ethane