The synthesis and optical properties of benzothiazole-based derivatives with various π-electron donors as novel bipolar fluorescent compounds

Novel bipolar benzothiazole-based derivatives with various π-electron donors were synthesized and characterized using 1H and 13C NMR and mass spectrometry; their thermal, optical and electrochemical properties were also investigated. Optoelectronic properties are reported and discussed in terms of the distribution of the highest occupied molecular orbital and the lowest unoccupied molecular orbital and the conjugative pathway between the electron-donating moieties and electron-accepting moieties. The compounds exhibited high fluorescence quantum yield, desirable HOMO levels and high thermal stability. Quantum chemical calculations were used to study optimized ground-state geometry as well as spatial distributions of HOMO and LUMO levels of the compounds.