Synthesis, Structures, Magnetic and Luminescent Properties of a Series of Iron(II) and Zinc(II) Coordination Frameworks with Versatile 4‐Substitued 1, 2,4‐Triazole Ligands

Abstract

AbstractThree multi‐dentate 1, 2,4‐triazole derivative ligands containing different 4‐substituted groups, namely N‐1, 2,4‐triazol‐4‐yl(pyridin‐3‐yl)methylenimine (L1), N‐1, 2,4‐triazol‐ 4‐yl(pyridin‐4‐yl)methylenimine (L2), and 4‐(2‐pyridine)‐1, 2,4‐triazole (L3) were used to isolate five iron(II) and zinc(II) coordination frameworks, [Zn(μ2‐L1)Cl2] (1), [Zn(μ2‐L2)Br2] (2), [Fe(L1)2(NCS)2(H2O)2] (3), [Fe(L3)2(dca)2(H2O)2] (4), and [Fe(L3)2(μ2‐dca)] (5) (dca = dicyanamide anion). When different zinc(II) salts were used to react with L1 and L2 under solvothermal conditions, two one‐dimensional (1D) zinc(II) coordination frameworks 1 and 2 containing four‐coordinate central zinc(II) atoms were isolated. 1 is a 3D achiral supra‐molecular framework, whereas 2 is a 3D chiral supra‐molecular framework containing helical chains on a 21 axis. 3 is a mono‐nuclear iron(II) coordination framework containing six‐coordinate central FeII atoms. When L3 was employed, mono‐nuclear iron(II) framework 4 and 1D iron(II) chain 5 could be isolated when different amounts of Nadca were introduced into the reaction system. Variable‐temperature magnetic susceptibility data of 3–5 were recorded in the 2–300 K temperature range indicating weak anti‐ferromagnetic interactions. The solid‐state luminescent properties of coordination polymers 1 and 2 were also investigated at room temperature.