Colorimetric and fluorimetric chemosensor based on upper rim-functionalized calix[4]arene for selective detection of fluoride ion.

A new colorimetric and fluorescent chemosensor for fluoride anion based on calix [4]arene bearing four sulfonamide-fluorenone subunits on the upper rim was conveniently synthesized. It showed a remarkable color change as well as the fluorescence quenching upon addition of F- even in the presence of a wide range of anions in DMSO. The binding property of L with F- was studied by a combination of various spectroscopic techniques, such as absorption and emission titration, Job's plot and 1H NMR titration. It is anticipated that this design with functional group attached to upper rim of calix[4]arene platform can provide a new approach for the development of F- chemosensor.