title: Synthesis and fluorosolvatochromism of 3-arylnaphtho[1,2-b]quinolizinium derivatives.
abstract: Cationic biaryl derivatives were synthesized by Suzuki-Miyaura coupling of 3-bromonaphtho[1,2-b]quinolizinium bromide with arylboronic acids. The resulting cationic biaryl derivatives exhibit pronounced fluorosolvatochromic properties. First photophysical studies in different solvents showed that the emission energy of the biaryl derivatives decreases with increasing solvent polarity. This red-shifted emission in polar solvents is explained by a charge shift (CS) in the excited state and subsequent solvent relaxation. Furthermore, the polarity of protic polar and aprotic polar solvents affects the emission energy to different extent, which indicates a major influence of hydrogen bonding on the stabilization of the ground and excited states.
authors.affiliation: Department of Chemistry and Biology, University of Siegen and Center of Micro and Nanochemistry and Engineering, Adolf-Reichwein-Str. 2, 57068 Siegen, Germany.
authors.forename: Phil M
authors.initials: PM
authors.lastname: Pithan
authors.affiliation: Department of Chemistry and Biology, University of Siegen and Center of Micro and Nanochemistry and Engineering, Adolf-Reichwein-Str. 2, 57068 Siegen, Germany.
authors.forename: David
authors.initials: D
authors.lastname: Decker
authors.affiliation: University of Padova, Department of Pharmaceutical and Pharmacological Sciences, via Marzolo 5, 35131 Padova, Italy.
authors.forename: Manlio Sutero
authors.initials: MS
authors.lastname: Sardo
authors.affiliation: University of Padova, Department of Woman's and Child's health, 35128 Padova, Italy.
authors.forename: Giampietro
authors.initials: G
authors.lastname: Viola
authors.affiliation: Department of Chemistry and Biology, University of Siegen and Center of Micro and Nanochemistry and Engineering, Adolf-Reichwein-Str. 2, 57068 Siegen, Germany.
authors.forename: Heiko
authors.initials: H
authors.lastname: Ihmels
keywords: fluorescence; heterocycles; quinolizinium; solvatochromism