Comparison of 1,4-distyrylfluorene and 1,4-distyrylbenzene analogues: synthesis, structure, electrochemistry and photophysicsElectronic supplementary information (ESI) available: NMR spectra; UV/vis absorption and PL emission spectra, additional DFT calculations, and details of refinement for single crystal X-ray diffraction structures. CCDC 930514-930515. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c3ob40580j

A series of nine 1,4-distyrylfluorene derivatives ( 2 ) functionalized with substituents of variable electron-donating 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. A series of nine 1,4-distyrylfluorene derivatives ( 2 ) functionalized with substituents of variable electron-donating or -accepting capabilities was synthesised.