Linear, two- and four-armed pyridine-decorated thiazolo[5,4-d]thiazole fluorophores: Synthesis, photophysical study and computational investigation

A novel family of thiazolo[5,4-d]thiazole (TzTz) fluorophores having a general formula (py)n-?-TzTz-?-(py)n (n = 1 or 2, py pyridine) is herein reported. The investigated compounds are decorated with alkoxy-substituted pyridine scaffolds bearing chains different lengths (a methoxy, b 2-ethylhexan-1-oxy, c 2-decyltetradecan-1-oxy) that connected at either the para- meta-position(s) phenyl bridging ring. feature linear 1, para-substituted, series 8), two-armed meta-substituted 9) four-armed 10) molecular architecture. Steady-state and time-resolved photophysical investigation employed to characterize optical properties in both diluted CH2Cl2 CH2Cl2:trifluoroacetic acid (TFA) 95:5 solutions, as well thin-film poly(methyl methacrylate) (PMMA) matrix 20 wt% doping. All display electronic transitions mainly ?-?* nature solution solid state. However, while peripheral pyridyl-phenyl moieties ?-TzTz-? core participate absorption transitions, emission involves mostly core. clear effect positional isomerism on observed, protonation pyridines offering further modulation. Thus, these results provide some useful hints design TzTz-based promising photoactive materials.