Synthesis and Hg2+ Recognition of Novel Azobenzene Derivatives Bearing Heterocyclic Units

Four novel azobenzene derivatives, 4,4'-bis(CH2SAr)azobenzene (Ar = different heterocyclic units), have been prepared and characterised by IR, 1H NMR, 13C NMR, MS and elemental analysis. Their complexation properties to different heavy and transition metal ions have been studied by UV and fluorescence spectra. The compound 4,4'-bis(4,6-dimethyl-pyrimidine-2-ylmethylthio)azobenzene shows selective recognition of Hg2+.