Insights into the solvents effect on spectral and photophysical properties of novel fluorescent heteroaromatic bis-peri-fused azoxonium cations

Aromatic fluorine atom-induced highly amine-sensitive trimethine cyanine dye showing colorimetric and ratiometric fluorescence change

“…The large difference in the reactivity was related to the Gutmann donor number (DN) and acceptor number (AN) of solvent molecules, which are the empirical measures of the nucleophilic and electrophilic properties of the solvents. 35,36 Solvents with high DN can stabilize cations, 37 while an opposite phenomenon is observed for AN. Therefore, the reaction of the dye with the amine is more likely to proceed in THF and DMSO, which have larger DN and/or smaller AN than acetone, MeOH, chloroform, and DCM, because the cationic dye is most involved in this system.…”

“…The large difference in the reactivity was related to the Gutmann donor number (DN) and acceptor number (AN) of solvent molecules, which are the empirical measures of the nucleophilic and electrophilic properties of the solvents. 35,36…”