title: Domino synthesis of protochromic "ON-OFF-ON" luminescent 2-styryl quinolines.
abstract: The microwave-assisted coupling-isomerization reaction (MACIR) opens a straightforward domino access to 2-styryl quinolines in good to excellent yields. The push-pull character of these lumophores can be enhanced by placing a dimethyl amino group as an auxochrome in the para-position of the styryl moiety whereas anti-auxochromes are located in the 6-position of the quinoline part. The optical absorption and emission properties of the compounds were studied in solvents of different polarity and at various pH. The pronounced proto- and solvochromicity of the absorption and emission properties qualify them as luminescent pH sensors with "ON-OFF-ON" emission profiles triggered by pH variation over a broad pH range. The electronic structure of the chromophores is rationalized by DFT calculations.
authors: Lehrstuhl für Organische Chemie, Institut für Organische Chemie und Makromolekulare Chemie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, D-40225 Düsseldorf, Germany.
authors: Rahime
authors: R
authors: Cinar
authors: Jan
authors: J
authors: Nordmann
authors: Elena
authors: E
authors: Dirksen
authors: Thomas J J
authors: TJ
authors: Müller
mesh_terms: D006863:Hydrogen-Ion Concentration; D007536:Isomerism; D049449:Luminescence; D049408:Luminescent Agents / Q000138:chemical synthesis*; D008872:Microwaves; D008958:Models, Molecular; D011804:Quinolines / Q000138:chemical synthesis*
chemical_list: D049408:Luminescent Agents; D011804:Quinolines; C481600:styrylquinoline