Colorimetric and fluorogenic anion sensors of 2′-(p-nitrophenyl)-imidazol[4′,5′-f]-1,10-phenanthroline[5,6-f] and its complex of

Abstract

2′-(p-nitrophenyl)-imidazol[4′,5′-f]-1,10-phenanthroline[5,6-f] (1) and its complex (2) were synthesised and studied for the anion sensing by UV–vis, fluorescence and ¹H NMR titration experiments. Compounds 1 and 2 exhibited obviously different changes between reactions with AcO⁻ , F⁻ , and with other halogens, i.e. Cl⁻ , Br⁻ , I⁻ , in any of the UV–vis, fluorescence and ¹H NMR titration spectra in DMSO experiments. With an 89 nm red shift, 1 was convenient to be employed to detect anions with the naked eye. Complexed with the electron withdrawing metal ion, 2 had the stronger interaction with anions to be detected than 1 had.

Keywords:

• anion sensor
• colorimetry
• fluorescence
• ¹H NMR
• X-ray structure

Acknowledgements

This work was supported by the National Natural Science Foundation of China (Nos. 20371028, 20671052) and the Natural Science Foundation of Tianjin of China (No. 023605811).