Synthesis and Photophysical Studies of Novel V‐Shaped 2,3‐Bis{5‐aryl‐2‐thienyl}(dibenzo[f,h])quinoxalines

Abstract A series of novel V‐shaped luminophores containing electron‐withdrawing dibenzo[ f,h ]quinoxaline core and arylthienyl donor fragments at positions 2 and 3 has been synthesized. The absorption spectra (UV/vis) were recorded in several solvents, whereas emission spectra were recorded in solutions and powders. The solvatochromism as well as halochromism of obtained compounds was also explored. Electronic‐structure calculations using quantum‐chemistry methods were performed to further analyse experimental results. All characteristics were compared with that of 2,3‐bis(arylthienyl)quinoxaline counterparts. The halochromic effect studies showed that upon gradual addition of trifluoroacetic acid (TFA) to the toluene solution of diethylaminophenyl‐substituted dibenzo[ f,h ]quinoxaline chromophore, absorption and emission changed. Observed band shifts were more distinct in the case of mentioned quinoxaline than for other derivatives. All of the (dibenzo[ f,h ])quinoxaline chromophores exhibited good sensitivity toward nitro‐containing explosives with high Stern‐Volmer constants up to 57800 M −1 , these results are remarkable for such heterocyclic systems.