Vol 44, No 1 (2018)

Self-assemblies of the flexible ferrocenyl block 2-chloro-4-ferrocenylbenzoate with Cd²⁺ cations in the presence of N-containing auxiliary ligand result in two coordination complexes, namely, &{[Cd(η² -OOCClH₃C₆Fc)₂(Mbbz)(CH₃OH)] · (H₂O)0.5}_n (I) and [Cd(η² -OOCClH₃C₆Fc)₂(Bbbm)]_n (II) {Fc = (η⁵- C₅H₄)Fe(η⁵-C₅H₄), Mbbz = 1,1'-methyl benzimidazole, Bbbm = 1,4-bis(benzimidazol-1-ylmethyl)-benzene}. Their structure has been determined by single-crystal X-ray diffraction analyses (CIF files nos. 1529095 (I), 1529096 (II)) and further characterized by elemental analyses, IR spectra, and thermogravimetric analyses. Crystallographic characterization shows that both I and II are 1D chain structures. Notably, various C–H···π interactions and C–H···Cl interactions are discovered in I and II, and they have significant contributions to self-assembly, which extend 1D complex to infinite 3D supramolecular networks. Moreover, the electrochemical studies of I and II in DMF solution display irreversible redox waves and indicate that the half-wave potentials of the ferrocenyl moieties in I and II are shifted to positive potential compared with that of free 2-chloro-4-ferrocenylbenzoate.

Two centrosymmetric dinuclear manganese(III) complexes, [Mn₂L₂(N₃)₂] (I) and [Mn₂L₂(NCS)₂] (II), where L is the deprotonated form of N,N'-bis(5-methylsalicylidene)propane-1,2- diamine (H₂L), have been prepared and structurally characterized by elemental analysis, IR and UV-Vis spectra and single crystal X-ray diffraction (СIF files CCDC nos. 1553014 (I), 1553015 (II)). The Mn atoms are in octahedral coordination. Catalytic properties for epoxidation of styrene by the complexes using PhIO and NaOCl as oxidant have been studied.

In the present study, two new zinc complexes with the chemical formulas of [Zn(2-Ampy)(Acac)₂] (I) and [Zn(p-Van)₂(H₂O)₂] (II) were synthesized and characterized by FT-IR, ¹H NMR, and UV-Vis spectroscopy. Moreover, the crystal structures of the complexes were determined by X-ray diffraction technique. Single-crystal X-ray diffraction analyses (CIF files CCDC nos. 1513672 (I) and 1513673 (II)) revealed that complex I has a distorted square pyramid environment, and complex II has a distorted octahedral geometry. The complexes were also screened for in vitro antibacterial activities against some bacteria. The results show that complexes have the effective antibacterial activities. The complexes were employed to prepare ZnO nanoparticles by the combustion synthesis method at 700°C for 8 h. The nanoparticles were characterized, using powder X-ray diffraction analysis (PXRD), scanning electron microscopy and transmission electron microscope. PXRD analysis showed the presence of pure phase in both samples. Furthermore, the crystallite size was approximately 37 and 42 nm for ZnO prepared from complexes I and II, respectively.

The reaction of CuCl₂ · 2H₂O with pyridine-2,4,6-tricarboxylic acid (H₃Pyta) in ethanol and water under hydrothermal synthesis conditions leads to the formation of a trinuclear copper polymer {[Cu₃(Pyta^3–)₂(H₂O)₈] · 4H₂O}n (I) (C₁₆H₂₈N₂O₂₄Cu₃, Mr = 823.05, ρ_calcd = 1.955 g cm^–3). The polymer was characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, and X-ray single-crystal diffraction (СIF file CCDC no. 1525203). The result showed that I belongs to the monoclinic system, P2₁/c space group. TGA curve shows that polymer I first removes water molecules, and then the ligand split for polymer I, and the remained residue is CuO. The magnetic measurement reveals the pyridine-2,4,6-tricarboxylic acid as bridge ligand can mediate the antiferromagnetic coupling interaction between magnetic centers.

A mononuclear coordination complex, quinidinum-zinc(II)-trichloride (I), and a multi-component ionic complex, quinidinum iron(III) tetrachloride hydrogen chloride hydrate (II), have been synthesized and characterized by elemental analyses, IR spectra, and single crystal X-ray diffraction (CIF files nos. 1497628 (I) and 1497629 (II)). The weak hydrogen-bonding interactions exist in both complexes I and II. Both complexes crystallize in the chiral space groups with the absolute configuration. Complex I crystallizes in the orthorhombic space group P2₁2₁2₁ with a = 7.6651(6), b = 11.4923(9), c = 24.653(2) Å, and Z = 4. Complex II crystallizes in the monoclinic space group P2₁ with a = 6.6425(15), b = 18.660(4), c = 10.958(3) Å, β = 104.973(3), and Z = 2.

Two new IB group metal coordination polymers, namely, {[Cu₃(TFMIDC)₂(H₂O)₂] · 4H₂O}n (I) and [Ag₂(HTFMIDC)(Py)]_n (II) (H₃TFMIDC = 2-(trifluoromethyl)-1H-imidazole-4,5-dicarboxylic acid, Py = pyridine), have been successfully prepared and structurally characterized by different techniques including single crystal X-ray diffraction (CIF files CCDC nos. 1545402 (I) and 1545403 (II)), IR spectra, and powder X-ray diffraction. Compound I features an interesting two-dimentional (2D) sheet containing 1D left-handed and right-handed helical chains, while compound II exhibits an infinite 1D zig–zag chain structure. Both two coordination polymers further stack through weak interactions to give rise to 3D supramolecular frameworks. Furthermore, the thermal stabilities of I and II as well as the photoluminescent property of II were also studied.