Synthesis of benzobisoxazole-based D-π-a-π-D organic chromophores with variable optical and electronic properties

摘要

A series of symmetrical D-π-A-π-D molecules comprised of benzo[1,2-d;4,5-d']bisoxazole (BBO) and various arylenevinylenes was synthesized via a Knoevenagel condensation of 2,6-dimethyl BBO and the corresponding aryl aldehydes. The resulting compounds had energy levels that were easily modulated and broad absorptions in the visible spectrum. They also demonstrated high fluorescence quantum yields in solution. The solvatochromism of several derivatives was examined in a number of solvents, and it was found that the emission of the triphenylamine derivative varied by almost 100 nm, depending on the polarity of the solvent. Collectively, these results indicate that the optical and electronic properties of benzobisoxazoles are readily tuned through the choice of aryl co-monomer.