| Summary: | A series of ten push-pull chromophores comprising 1<i>H</i>-cyclopenta[<i>b</i>]naphthalene-1,3(2<i>H</i>)-dione as the electron-withdrawing group have been designed, synthesized, and characterized by UV-visible absorption and fluorescence spectroscopy, cyclic voltammetry and theoretical calculations. The solvatochromic behavior of the different dyes has been examined in 23 solvents and a positive solvatochromism has been found for all dyes using the Kamlet-Taft solvatochromic relationship, demonstrating the polar form to be stabilized in polar solvents. To establish the interest of this polyaromatic electron acceptor only synthesizable in a multistep procedure, a comparison with the analog series based on the benchmark indane-1,3-dione (1<i>H</i>-indene-1,3(2<i>H</i>)-dione) has been done. A significant red-shift of the intramolecular charge transfer band has been found for all dyes, at a comparable electron-donating group. Parallel to the examination of the photophysical properties of the different chromophores, a major improvement of the synthetic procedure giving access to 1<i>H</i>-cyclopenta[<i>b</i>]naphthalene-1,3(2<i>H</i>)-dione has been achieved.
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