Four luminescent metal-organic chain compounds based on semi-rigid N-donor ligands and 3-hydroxy-2-naphthoic acid for recognition of Fe3+ and Cr2O72- ions

Four luminescent metal-organic complexes based on semi-rigid N-donor ligands and 3-hydroxy-2-naphthoic acid (3-HNA), [Zn(bimb)(3-HNA)(2)] (1), [Zn(bbimb)(3-HNA)(2)]center dot 3H(2)O (2), [Zn(bimbp)(3-HNA)(2)] (3), [Cd(bimbp)(3-HNA)(2)] (4) [bimb = 1,4-bis(1-imidazol-yl-methyl)benzene, bimbp = 4,4'-bis(1H-imidazol-1-yl-methyl)biphenyl, bbimb = 1,4-bis(1-benzimidazolyl-yl-methyl)benzene], have been synthesized solvothermally. The 1D chain structures of complexes 1-4 exhibit the Z-type or linear geometry configurations, where the combination of the N-donor ligands and transition metal ions is regarded as the backbones, and the 3-HNA ligands are dangled covalently on both sides of such backbone. The investigation on the luminescence properties indicates that complexes 1-4 have luminescent detection capabilities against Fe3+ and Cr2O72- ions in DMF with excellent selectivity and sensitivity. (C) 2020 Elsevier Ltd. All rights reserved.