title: Synthesis and photoswitching studies of difurylperfluorocyclopentenes with extended π-systems.
abstract: In an attempt to design molecular optoelectronic switches functioning in molecular junctions between two metal tips, we synthesized a set of photochromic compounds by extending the π-system of 1,2-bis-(2-methyl-5-formylfuran-3-yl)perfluorocyclopentene through suitable coupling reactions involving the formyl functions, thereby also introducing terminal groups with a binding capacity to gold. Avoiding the presence of gold-binding sulphur atoms in the photoreactive centre, as they are present in the frequently used analogous thienyl compounds, the newly synthesized compounds should be more suitable for the purpose indicated. The kinetics of reversible photoswitching of the new compounds by UV and visible light was quantitatively investigated in solution. The role of conformational flexibility of the π-system for the width of the UV/Vis spectra was clarified by using quantum chemical calculations with time-dependent (TD)-DFT. As a preliminary test of the potential of the new compounds to serve as optoelectronic molecular switches, monolayer formation and photochemical switching on gold surfaces was observed by using surface plasmon resonance.
authors.affiliation: Fachbereich Chemie, Universität Konstanz, Konstanz, Germany.
authors.forename: Dmytro
authors.initials: D
authors.lastname: Sysoiev
authors.forename: Artem
authors.initials: A
authors.lastname: Fedoseev
authors.forename: Youngsang
authors.initials: Y
authors.lastname: Kim
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Exner
authors.forename: Johannes
authors.initials: J
authors.lastname: Boneberg
authors.forename: Thomas
authors.initials: T
authors.lastname: Huhn
authors.forename: Paul
authors.initials: P
authors.lastname: Leiderer
authors.forename: Elke
authors.initials: E
authors.lastname: Scheer
authors.forename: Ulrich
authors.initials: U
authors.lastname: Groth
authors.forename: Ulrich E
authors.initials: UE
authors.lastname: Steiner