Two Co(Ⅱ) Coordination Polymers Based on 3,5-Di(4H-1,2,4-triazole-4-yl)benzoic Acid Ligand: Syntheses,Structures and Magnetic Property

Two Co(Ⅱ) coordination polymers, namely [Co(L)Cl]_n(1) and [Co(L)(CH_3 COO)]_n(2), {HL = 3,5-di(4 H-1,2,4-triazole-4-yl)benzoic acid}, were synthesized under hydrothermal conditions. Compound 1 crystallizes in orthorhombic system, space group Pmma with a = 7.032(5), b = 11.555(8), c = 8.185(5) ?, V = 665.1(7) ?~3, Z = 2, Dc = 1.746 g/cm3~, F(000) = 350, Mr = 349.61, μ = 1.504 mm~(-1), the final R = 0.0568 and w R = 0.1739 for 2312 observed reflections with I 2σ(I). Compound 2 crystallizes in orthorhombic system, space group Pmma with a = 7.7505(17), b = 11.391(3), c = 8.0298(18) ?, V = 708.9(3) ?~3, Z = 2, Dc = 1.748 g/cm~3, F(000) = 378, Mr = 373.20, μ = 1.245 mm-1, the final R = 0.0350 and w R = 0.0873 for 5239 observed reflections with I 2σ(I). Single-crystal X-ray analyses revealed that complexes 1 and 2 exhibit similar 2 D layer structures with uncoordinated carboxyl as dangling arms. The neighboring layers are further connected by these arms, leading to interest 2 D → 3 D polythreading frameworks. Moreover, the magnetic susceptibility study indicates compound 1 exhibits antiferromagnetic behavior.     

Synthesis and Crystal Structure of 3,3＇-Bis（2-benzimidazolyl）-2,2＇-dipyridine with Hydrated Zinc（Ⅱ） Perchlorate

The reaction of Zn(ClO4)2·6H2O with 3,3'-bis(2-benzimidazolyl)-2,2'-dipyridine (L) gave a mononuclear zinc(II) complex: [ZnL2](ClO4)2·2DMF·4H2O, which was structurally characterized by EA, IR, UV, 1H NMR, fluorescence spectrum and single-crystal X-ray diffraction. The crystal (C54H54Cl2N14O14Zn, Mr = 1259.38) belongs to the monoclinic system, space group C2/c with a = 20.874(2), b = 14.9953(16), c = 20.462(3) , β = 101.553(2)°, V = 6274.8(13) 3, Z = 4, Dc = 1.333 g/cm3, F (000) = 2608, μ(MoKα) = 0.548 mm–1, R = 0.0682 and wR = 0.1931 for 4984 observed reflections with I > 2σ(I). The Zn(II) is four-coordinated in a slightly distorted tetrahedral geometry through four N atoms from four benzimidazole units of two ligands. In the crystal lattice, the [ZnL2]2+ cations are linked to each other by extensive intermolecular hydrogen bonds between nitrogen atoms of benzimidazole rings, water and DMF molecules.     

Hydrothermal Synthesis and Crystal Structure of a New Three-dimensional Heterometallic Coordination Polymer

A new 3d-4f heterometallic polymer {[Sm2Cu(PDC)2(SO4)2(H2O)6]·2H2O}n 1 has been synthesized by Sm2O3, Cu(SO4)2·5H2O and pyridine-3,5-dicarboxylic acid under hydrothermal conditions. The compound crystallizes in triclinic system, space group P1, with a = 6.352(7), b = 10.040(10), c = 10.315(11) , α = 94.958(14), β = 95.556(7), γ = 99.747(14)°, V = 641.7(12)3, Z = 1, Mr = 1030.63, Dc = 2.651 Mg/m3, μ = 5.615 mm-1, F(000) = 491, the final R = 0.0491 and wR = 0.1345 for 2098 observed reflections with I > 2σ(I). The compound is a three-dimensional network structure in which infinite lanthanide-carboxylate chains are linked by [Cu(SO4)2]2- metalloligands to form a mixed-metal coordination network.