Twisted Schiff-base macrocycle showing excited-state intramolecular proton-transfer (ESIPT): assembly and sensing properties.

A Schiff-base macrocyclic host (MH) showing ESIPT and AIEE is reported for the first time; the fluorescent macrocycle exhibited good pH tolerance and could serve as a probe for Cu2+ and Fe3+ ion sensing and removal. In addition, a series of size-tunable nanoparticles was fabricated by the self-assembly of free MH and its coordination complex with Fe3+ in THF/water solution.