Fluorescence sensing of by a imidazolium-based cholestane receptor

A new imidazolium functionalized cholestane-based receptor 3 has been synthesized and characterized. A binding study of receptor 3 with various anions was assessed by UV–vis and fluorescence spectroscopy in dry CH3CN and aqueous CH3CN solutions. Of all anions, 3 showed the highest binding constant with dihydrogen phosphate (Ka = 1.6 × 105 M−1) accompanying a colour change in a dry CH3CN solution.