Chemosensor properties of 7-hydroxycoumarin substituted cyclotriphosphazenes?

摘要

The newly synthesized cyclotriphosphazene cored coumarin chemosensors 5, 6 , and 7 were successfully characterized by $^{1}$H NMR, $^{31}$P NMR, and MALDI-TOF mass spectrometry. Additionally, the photophysical and metal sensing properties of the targeted compounds were determined by fluorescence spectroscopy in the presence of various metals (Li$^{+}$ , Na$^{+}$ , K$^{+}$ , Cs$^{+}$ , Mg2$^{+}$ , Ca2$^{+}$ , Ba2$^{+}$ , Cr3$^{+}$ , Mn2$^{+}$ , Fe3$^{+}$ , Co2$^{+}$ , Al3$^{+}$ , Hg$^{+}$ , Cu2$^{+}$ , Zn2$^{+}$ , Ag$^{+}$ , and Cd2$^{+}$) . The fluorescence titration results showed that compounds 5, 6 , and 7 could be employed as fluorescent chemosensors for Fe3$^{+}$ ions with high sensitivity. The complex stoichiometry between final cyclotriphosphazene chemosensors and Fe3$^{+}$ ions was also determined by Job's plots.