Bis(pyridylvinyl)diaminobenzenes: synthesis, acidochromism and solvatochromism of the fluorescence

Acidochromism of stilbenoid chromophores with a p‐aminoaniline centre

“…Complexation with Lewis acids or protonation has been shown to cause significant changes of the UV/Vis-absorption and emission spectra of p-conjugated chromophores with the basic site on the terminal positions. [9][10][11][12] Herein, we report the synthesis of oligo(phenylenevinylene)s (OPVs) with a central phenylene-1,4-diamine unit and the impact of interaction with protons on their optical spectra.…”

Tyrosine-derived stimuli responsive, fluorescent amino acids

“…S4, ESI † ) and emission bands upon addition of p TSA and can be explained by the protonation enhances the accepting effect of the pyridine, thus increasing intramolecular charge transfer from the donor to the pyridinium moiety (acceptor). 20 For the protonated species, the emission is partially quenched (QY = 10%) when compared to its neutral state (QY = 45%). Conversely, addition of NaOH enriched the phenolate population and as a result of extended conjugation, compound 5f exhibited a more intense (QY = 57%) and red shifted emission at 630 nm.…”

Thermostability and photophysical properties of mixed-ligand carboxylate/benzimidazole Zn(II)-coordination polymers

“…Moreover, both polymers contain benzimidazole in different forms; protonated in the case of (1) and deprotonated in (2). It has been reported that the protonation of the heterocyclic p-conjugated systems may cause significant shifts of emission bands also in the solid state [47].…”