Synthesis of Novel Rod-Shaped and Star-Shaped Fluorescent Phosphane Oxides - Nonlinear Optical Properties and Photophysical Properties

The design of a new class of fluorophores is presented. Some push–pull chromophores (D–π–A) containing polyphenylethynyl units and a phosphane oxide moiety were efficiently prepared from common intermediates. Straightforward syntheses gave novel one‐armed, rod‐shaped and three‐armed, star‐shaped fluorophores. The optical properties of the resulting star‐shaped derivatives were evaluated, showed high fluorescence quantum yields, and their excitation induces very efficient charge redistribution. Moreover, thanks to their push–pull character, the molecules exhibited significant second‐order NLO properties with good transparency, up to 67⋅10−30 esu at 1907 nm, with an absorption λmax at 369 nm. The effect of the donor group and of the number of phenylethynyl arms have been studied in this work.