5-[{(2-Hydroxynaphthalen-1-yl)methylene}amino]pyrmidine-2,4(1H,3H)-dione as Al3+ selective colorimetric and fluorescent chemosensor

The synthesis and characterization of 5-[{(2-hydroxynaphthalen-1-yl)methylene}amino]pyrmidine-2,4(1H,3H)-dione (AMN), a tridentate Schiff base fluorescent sensor for selective determination of Al3+ in acetonitrile as well as in aqueous solution have been described. The AMN was characterized by IR, NMR, UV–vis and ESI-mass spectral analyses. UV–vis, fluorescence and 1H NMR titrations were performed to study the binding mode of AMN with Al3+. The AMN shows an enhanced fluorescence in the presence of Al3+ and forms 1:1 complex with Al3+. Other cations Na+, K+, Ca2+, Cr3+, Mn2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+ and Hg2+ show no appreciable change in fluorescence intensity. The lowest detection limit for Al3+ in acetonitrile and water was determined to be 3.2 × 10−7 M and 1 × 10−6 M, respectively.