A phenylbenzoxazole–amide–azacrown linkage as a selective fluorescent receptor for ratiometric sensing of Pb(ii) in aqueous media

Abstract

A phenylbenzoxazole-amide-azacrown linkage (L) acts as a fluorescent receptor for ratiometric Pb(2+) sensing in aqueous media. This is promoted by the excited state intramolecular proton transfer (ESIPT) of the amide proton to benzoxazole nitrogen via coordination of Pb(2+) with amide oxygen.