Preparation and ion recognition features of porphyrin–chalcone type compounds as efficient red-fluorescent materials

A series of porphyrins containing an α,β-unsaturated ketone unit in a β-pyrrolic position ( 4a–e ) were synthesized and characterized. Their sensing ability towards Ag + , Cu 2+ , Zn 2+ , Cd 2+ , and Hg 2+ was evaluated in solution by absorption and fluorescence spectroscopy and in the gas phase using MALDI-TOF-MS spectrometry. The versatility of these types of compounds towards other metals was also analysed by studying the behaviour of compound 4d in the presence of Na + , K + , Tl + , Ca 2+ , Mg 2+ , Mn 2+ , Co 2+ , Ni 2+ , Pb 2+ , Fe 2+ , Fe 3+ , Cr 3+ and Al 3+ . Polymeric films of polymethylmethacrylate (PMMA) doped with ligand 4d were prepared and their ability to be used as metal ion-probes in the solid state was studied. Compounds of type 4 showed the best performance to be analytically used in developing new Zn 2+ ratiometric molecular devices.