Synthesis and photophysical properties of isocoumarin-based D-π-A systems

• DOI: 10.1016/j.dyepig.2019.107917
• Publication Date: 2019-09-21T21:37:27Z
• Authors: Valentina Pirovano; Marialaura Marchetti; Jessica Carbonaro; Elisa Brambilla; Elisabetta Rossi; Luca Ronda; Giorgio Abbiati
• Keywords: Isocoumarin; Solvatochromism; Silver catalysi; Polarity sensitive; Push-pull system; Isocoumarins; Polarity sensitive; Push-pull system; Silver catalysis; Solvatochromism; Fluorescence; 540; 01 natural sciences; Fluorescence; 0104 chemical sciences

Abstract We prepared a small library of polarity-sensitive fluorescent dyes characterized by an isocoumarin core properly functionalized with a conjugated push-pull system. The key step of the synthesis is based on a regio-selective silver(I)/p-TSA co-catalyzed cyclization of 2-alkynylbenzoates recently optimized in our laboratory. The photophysical properties of isocoumarin-based D-π-A systems have been investigated and a rationale was proposed based on their dipole moments and Hammett constants of the ED and EW groups involved.