title: Synthesis, electronic properties, and reactivity of phospholes and 1,1'-biphospholes bearing 2- or 3-thienyl C-substituents.
abstract: Two series of phospholes and 1,1'-biphospholes bearing either 2- or 3-thienyl substituents at the C atoms are prepared by using the Fagan-Nugent route. Their optical (UV/Vis absorption, fluorescence spectra) and electrochemical properties are systematically evaluated. Of particular interest, the first ever reported 3-thienyl-substituted phospholes exhibit higher LUMO levels than their 2-thienyl analogues, and show accordingly different physical properties. This study also reveals that the 1,1'-biphospholes exhibit sigma-pi conjugation. The phosphole and 1,1'-biphosphole derivatives bearing 3-thienyl substituents are characterized by X-ray diffraction study. The structure-property relationship established following the experimental data are fully supported by theoretical studies including time-dependent(TD)-DFT spectra. A photocyclization reaction performed on the thioxo- and oxophospholes having 3-thienyl substituents affords a novel ring-fused phosphole-thiophene derivative, which was characterized by an X-ray diffraction study. The structure and electronic properties of this novel dithienophosphole are discussed based on experimental and theoretical data.
authors.affiliation: Sciences Chimiques de Rennes, UMR 6226 CNRS-Université de Rennes 1, Campus de beaulieu, 35042 Rennes Cedex, France.
authors.forename: Omrane
authors.initials: O
authors.lastname: Fadhel
authors.forename: Dénes
authors.initials: D
authors.lastname: Szieberth
authors.forename: Valérie
authors.initials: V
authors.lastname: Deborde
authors.forename: Christophe
authors.initials: C
authors.lastname: Lescop
authors.forename: László
authors.initials: L
authors.lastname: Nyulászi
authors.forename: Muriel
authors.initials: M
authors.lastname: Hissler
authors.forename: Régis
authors.initials: R
authors.lastname: Réau