Fluorinated metal–organic frameworks of 1,4-bis(1,2,4-triazol-1-ylmethyl)-2,3,5,6-tetrafluorobenzene: synergistic interactions of ligand isomerism and counteranions

Abstract

A fluorinated bis(triazole) ligand, 1,4-bis(1,2,4-triazol-1-ylmethyl)-2,3,5,6-tetrafluorobenzene (Fbtz), was applied to coordinate with a series of Mn(II), Co(II), Fe(II), and Cu(II) ions, respectively. In comparison with its nonfluorinated analogue 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene (btx), Fbtz is able to build six novel metal-organic frameworks by acting as a versatile bridge combining with the terminal chlorides (1-5) or acetates (6) ligands. The solid-state crystal structures of 1-6 are studied by single-crystal X-ray crystallography to form the following structures: 3D polymers [M(Fbtz)2Cl2]n (1: M = Mn, 2: M = Co), 1D double chain polymers {[M(Fbtz)2Cl2]·CH2Cl2·xH2O}n (3: M = Co, x = 1; 4: M = Fe, x = 2), {[Cu(Fbtz)2Cl2]·4H2O}n (5), and a 1D double-stranded helical polymer {[Cu2(Fbtz)(OAc)2]·2H2O}n (6). Conformations of Fbtz in 1-6 can be tuned as a result of varying the anions or solvent system, which ultimately form a series of novel coordination frameworks with different supramolecular architectures. The antibacterial activities of all complexes are investigated. Complexes 4 and 5 show a wide range of bactericidal activities to Gram positive (B. subtilis and S. aureus) and negative (E. coli and P. fluorescence) bacterial strains. The synergistic interactions of ligand isomerism and counteranions have profound effects on the supramolecular networks and properties.

Zn(II)/Cd(II) Terephthalate Coordination Polymers Incorporating Bi-, Tri-, and Tetratopic Phenylamine Derivatives: Crystal Structures and Photoluminescent Properties

“…Other tetratopic, − pentatopic, , hexatopic, − and octatopic , carboxylates have also been widely utilized as multidentate linkers, generating various topological structures with potential properties. At the same time, ditopic and tritopic N-donor ligands based on 1,2,4-triazoles, which combine the coordination geometries of both imidazoles and pyrazoles to arrange their three heteroatoms, have been extensively studied. − However, to the best of our knowledge, coordination polymers based on polytopic 1,2,4-triazole-containing ligands with phenylamine backbones have not been investigated systematically much to date …”