title: Comparison of 1,4-distyrylfluorene and 1,4-distyrylbenzene analogues: synthesis, structure, electrochemistry and photophysics.
abstract: A series of nine 1,4-distyrylfluorene derivatives (2) functionalized with substituents of variable electrondonating or -accepting capabilities was synthesised. The photophysical properties of the molecules were investigated, including UV/vis absorption, photoluminescence emission, and fluorescence quantum yields. Photophysical properties of chromophores 2 were found to exhibit significant solvatochromic effects, especially in the Stokes shift and photoluminescence maxima. The electrochemical properties of series 2 were also assessed by cyclic voltammetry and differential pulse voltammetry. Results of photophysical and electrochemical analyses were further supported by DFT calculations (B3LYP/6-31G*) and single crystal X-ray diffraction on select molecules. The contributions of intermolecular π-stacking and hydrogen bonding to crystal packing are discussed. A series of nine 1,4-distyrylphenylene derivatives (3) were also synthesised and similarly characterized for comparison to photophysical and solvatochromic effects observed in series 2. Properties of similarly-substituted molecules in series 2 and 3 were compared to one another in order to assess the influence of the 1,4-fluorenylene unit.
authors.affiliation: Department of Chemistry, Clemson University, Clemson, South Carolina 29634, USA.
authors.forename: Brynna J
authors.initials: BJ
authors.lastname: Laughlin
authors.forename: Tyler L
authors.initials: TL
authors.lastname: Duniho
authors.forename: Samantha J
authors.initials: SJ
authors.lastname: El Homsi
authors.forename: Benjamin E
authors.initials: BE
authors.lastname: Levy
authors.forename: Nihal
authors.initials: N
authors.lastname: Deligonul
authors.forename: Joshua R
authors.initials: JR
authors.lastname: Gaffen
authors.forename: John D
authors.initials: JD
authors.lastname: Protasiewicz
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Tennyson
authors.forename: Rhett C
authors.initials: RC
authors.lastname: Smith