The cholesterol appended hydroxybenzaldehyde derived Schiff bases1–4have been designed and synthesized. They are suitable for the naked-eye detection of metal ions such as Hg2+and Ag+using sol–gel methodology involving either rupturing or maintaining the imine bonds.
A T-shaped Schiff-base triazatruxene derivative (TATNFF) was designed, synthesized, and explored as a sensitive probe to detect HCl gas by the naked eye.