Excited state proton transfer dye lasers

Excited state intramolecular proton transfer in amino 2-(2′-hydroxyphenyl)benzazole derivatives: Effects of the solvent and the amino group position

“…Compounds emitting fluorescence through the excitedstate intramolecular proton transfer (ESIPT) mechanism [1][2][3][4][5][6] have become a very attractive field of research by virtue of the widespread applications that can be envisaged for these dyes, such as UV-light polymer stabilizers [7,8], sensors [9] and laser dyes [10]. Particular interest has recently been shown in a new class of ESIPT amino benzazole derivatives, where applications such as fluorescent probes to label proteins and DNA [11] and new polymeric materials [12,13] were also reported.…”

Novel ESIPT fluorescent benzazolyl-4-quinolones: Synthesis, spectroscopic characterization and photophysical properties

“…Intramolecular proton transfer occurs when a molecule contains both an acidic and a basic site which, upon electronic excitation, experience enhanced acidity or basicity, respectively [21] The excited keto tautomer (K 1 ) decays, therby emitting fluorescence as the fundamental keto tautomer (K 0 ), and the initial enol form (E 0 ) is regenerated [22,23]. Since most ESIPT processes are reversible, these systems have found application as UV-light stabilizers [24,25], laser dyes [26], sensors [27], DNA probes [28,29], in drug delivery systems [30], hybrid materials [31] and also as fluorescent probes [32][33][34][35].…”

New fluorescent monomers and polymers displaying an intramolecular proton‐transfer mechanism in the electronically excited state. III. Thermogravimetric stability study of the benzazolylvinylene derivatives

“…ESIPT-exhibiting molecules often present a large Stokes shift. This phenomenon has widespread implications in UV-light stabilizers, 6,7 laser dyes, 8 new polymeric materials, 9 -11 and also as fluorescent probes to labeling proteins. 12,13 The UV light absorption through the enol conformer (E) produce the excited enol (E*), which is quickly converted to an excited keto tautomer (K*) by an intramolecular proton transfer.…”