Cholesterol‐Modified Quinazoline: Gelation, Ag⁺ and Al³⁺ Ion Detection under Different Conditions and Phase Selective Dye Removal with an Ag‐gel

Abstract

A newly designed cholesterol-based quinazoline system 1 has been synthesized. The gelation ability of the compound 1 has been examined in different solvents. It exhibits strong gelation with silver perchlorate in benzene and acts as excellent visual detector of Ag + ions over a series of other metal ions examined. The compound 1 selectively detects Al 3 + ion as well with significant fluorometric response and color change. The benzene gel of 1 exhibits good viscoelastic response. In rheological study, the values of G' are observed to be 8 times higher than those of G'' at any frequency which signify dominant elastic character of the gel. The mode of aggregation of 1 during gelation in the presence of Ag + ions and the binding of Al 3 + ion in solution are explained by several spectroscopic techniques such as UV-vis, fluorescence, FTIR and NMR. Theoretical study further enlightens the observations. As application, Ag-gel shows excellent ability to remove toxic dyes from water.