Selective Zn2+ Recognition of Novel Triazole Schiff-Base Derivatives Bearing the Coumarin Group

Three novel triazole Schiff-bases derivatives bearing coumarin units have been synthesised from 3,5-diaryl-4-amino-1,2,4-triazole with three kinds of coumarin aldehydes. The UV-Vis absorption and fluorescence emission spectra of (E)-4-((3,5-diphenyl-4H-1,2,4-triazol-4-ylimino)methyl)-7-methoxy-2H-chromen-2-one exhibited blue-shifted absorption and fluorescent enhancement upon chelation to zinc ion as a 2: 1 ligand-to-metal complex with a binding constant of 3.29 × 106 M−1.