Study on Fluorescence Polarity Probes of Two Carbazole Pyridine-N-Oxide Internal Salts
This article synthesized two carbazole pyridine N-oxide internal salts,4-(9H carbazole 9-yl)pyridine 1-oxide(CPNO)and 4-(4-(9H carbazole 9-yl)phenyl)pyridine 1-oxide(CPPNO).It measured their UV visible absorption and fluorescence spectra in different solvents,showing good sensitivity to solvent polarity.The calculation shows that both compounds have a sizeable excited state dipole moment,which is the reason for the solvent polarity sensitivity of the compound.The research results provide a new approach for developing novel fluorescent polarity probes.