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Four new hetero-pentanuclear 3d–4f complexes [Zn4(L)2La(NO3)2(OEt)(H2O)] (1), [Zn4(L)2Ce(NO3)2(OMe)(MeOH)] (2), [Zn4(L)2Pr(NO3)2(OEt)(EtOH)] (3) and [Zn4(L)2Nd(NO3)2(OMe)(MeOH)] (4) were synthesized by the reactions of a newly synthesized octadentate bis(salamo)-based tetraoxime ligand (H4L) with Zn(OAc)2·2H2O and Ln(NO3)3·6H2O (Ln = La, Ce, Pr and Nd), respectively, and characterized via elemental analyses, FT-IR, UV-Vis spectroscopy and single crystal X-ray crystallography. The X-ray crystallographic investigation revealed that all ZnII ions were located in N2O3 coordination spheres, and possessed a trigonal bipyramid coordination environment. The LnIII ion lay in an O8 coordination sphere, and adopted a distorted square antiprismatic coordination environment. Furthermore, supramolecular interactions and fluorescence properties were investigated.

Two newly di- and tri-nuclear Cu(II) and Ni(II) complexes constructed from a half-salamo chelating ligand (HL: 2-[O-(1-ethyloxyamide)]oxime-6-methoxyphenol), [Cu2(L)2(μ-OAc)2] (1) and [{Ni3(μ-OAc)2(L)2(OAc)2]·CHCl3 (2), and one tetranuclear Co(II) complex [Co4(L′)4(MeOH)4] (3) based on an unexpected ligand H2L′ derived from the cleavage of HL have been synthesized and characterized by elemental analyses, IR, UV–vis spectra, and single crystal X-ray diffraction analyses. The single crystals of complexes 1, 2 and 3 in the process of synthesis are obtained through different routes. The complex 1 includes two Cu(II) atoms, two completely deprotonated (L)− units and two μ-acetate ions, which displays a propeller-type motif. The complex 2 contains three Ni(II) atoms, two completely deprotonated (L)− units, two μ-acetate ions, two chelating acetate ions and one crystallizing chloroform molecule, the crystal structure of complex 2 reveals a butterfly-type motif. The complex 3 is made up of four Co(II) atoms, four completely deprotonated (L′)2− units (HL′: 2-[O-(1-hydroxyethyl)]oxime-6-methoxyphenol) and four coordinated methanol molecules, which shows a windmill-type motif. Besides, magnetic properties and Hirshfeld surface analyses were discussed.

C60H50Co2N9O15, triclinic, P1̅ (no. 2), a = 13.6074(19) Å, b = 13.9185(17) Å, c = 15.837(2) Å, α = 81.196(4)°, β = 86.607(4)°, γ = 81.665(4)°, Z = 2, V = 2930.7(7) Å3, R gt(F) = 0.0564, wR ref(F 2) = 0.2010, T = 296(2) K.

The Schiff base binuclear Zn(II) complexes, [Zn2(L)2∙(H2O)2]∙2DMF (1) and its coordination polymer [Zn2(L)2∙(4,4′-bpy)2]n (2) (H2L = 3-[(5-chloro-2-hydroxy-benzylidene)-amino]-4-hydroxy-chromen-2-one, 4,4′-bpy = 4,4′-bipyridine), were synthesized under the same experimental condition without or with the auxiliary ligand 4,4′-bpy, respectively. The structural analysis revealed that complexes 1 and 2 have different crystal structures. The complex 1 was a centrosymmetric binuclear structure. It is noteworthy that the linker 4,4′-bpy was introduced during the synthesis of complex 2, so that two water molecules in complex 1 were replaced by two 4,4′-bpy linkers to form one-dimensional (1D) chain-like coordination polymer. The central Zn(II) ions in complex 1 were penta-coordinated distorted square pyramid geometry with τ = 0.42. However, the Zn(II) ions of complex 2 were hexa-coordinated distorted octahedral geometry. The fluorescence spectrum showed the complex 2 containing 4,4′-bpy was substantially quenching of the fluorescence as compared with the complex 1. In addition, it could be seen from the DFT calculation the energy gaps of the complexes 1 and 2 were both reduced compared to the ligand H2L. However, the LUMO and HOMO orbits of the complex 2 were occupied by the 4,4′-bpy, which is different from complex 1, resulting in 1 and 2 had different spectral properties.

A novel Schiff-base oxime sensor H2L with the ONON chelating moieties was designed and synthesized based on condensation reaction. Different methods such as elemental analyses, FT-IR, 1H and 13C NMR were fully utilized in characterizing the structure of sensor H2L. The UV–vis spectra of the Zn2+ complex exhibit four clear isosbestic points which may be assigned to the ONON moieties binding to Zn2+. Sensor H2L operates on the CHEF and PET mechanisms, and the tendency of Zn2+ to strongly enhance fluorescence of sensor H2L was explored. Fluorescence measurements show that sensor H2L has excellent fluorescent selectivity for Zn2+ over many other metal ions based on intramolecular charge-transfer, and the results demonstrate that the binding between sensor H2L and Zn2+ is chemically reversible. The crystal structure of the Zn2+ complex has been characterized by X-ray crystallography.

Two novel mono- and heptanuclear Ni(II) complexes, [Ni(HL1)2(EtOH)2]·2EtOH (1) and [Ni7(L2)3(μ3-OMe)2(μ3-OH)6(MeOH)6] (2), have been synthesized by the reaction of Ni(II) acetate with H2L1 and H2L2, respectively. In the Ni(II) complex 1, the ligand H2L1 was partially deprotonated, only NO donor atoms of one salicylidene moiety of the (HL1)− unit coordinate to Ni(II) atom. While all the three H2L2 ligands in the Ni(II) complex 2 were completely deprotonated. The seven Ni(II) atoms are all hexa-coordinated, and have two coordination environments. The fluorescence properties of the ligands, the Ni(II) complexes 1 and 2 have been discussed.

C38H38Mn2N2O14, triclinic, P1̅ (no. 2), a = 8.2828(12) Å, b = 10.428(2) Å, c = 12.152(3) Å, α = 113.44(2)°, β = 93.369(16)°, γ = 107.890(16)°, Z = 1, V = 896.5(3) Å3, R gt(F) = 0.0578, wR ref(F 2) = 0.1288, T = 293(2) K.

C52H42CuN4O4, monoclinic, I12/c1 (no. 15), a = 21.8573(13) Å, b = 5.8605(4) Å, c = 33.683(2) Å, β = 97.428(5)°, Z = 4, V = 4278.4(5) Å3, R gt(F) = 0.0554, wR ref(F 2) = 0.1255, T = 293(2) K.

C38H36Cr2N2O14, triclinic, P1̄, a = 8.2863(13) Å, b = 10.4324(13) Å, c = 12.152(3) Å, α = 113.420(13)°, β = 93.326(13)°, γ = 107.857(12)°, Z = 1, V = 897.7(2) Å3, R gt(F) = 0.0454, wR ref(F 2) = 0.1112, T = 293(2) K.

C38H34Ni2Cl2N4O12, monoclinic, C2/c (no. 15), a = 17.867(3) Å, b = 9.170(6) Å, c = 24.651(5) Å, β = 110.837(2)°, Z = 4, V = 3775(3) Å3, R gt(F) = 0.0323, wR ref(F 2) = 0.1078, T = 293(2) K.

C38H38Co2N2O14, monoclinic, P21/n (no. 14), a = 9.7459(5) Å, b = 7.9026(7) Å, c = 24.0622(15) Å, β = 100.260(5)°, Z = 2, V = 1823.6(2) Å3, R gt(F) = 0.0576, wR ref(F 2) = 0.1201, T = 293(2) K.

C46H38MnN3O8, triclinic P1̅ (no. 2), a = 8.9705(6) Å, b = 12.0309(8) Å, c = 18.4209(13) Å, α = 96.303(2)°, β = 103.884(2)°, γ = 101.636(2)°, Z = 2, V = 1864.0(2) Å3, R gt(F) = 0.0496, wR ref(F 2) = 0.1274, T = 296 K.

C38H38Zn2N2O14, monoclinic, P21/n (no. 14), a = 9.6906(6) Å, b = 7.9055(5) Å, c = 24.0501(18) Å, β = 99.878(7)°, Z = 2, V = 1815.1(2) Å3, R gt(F) = 0.0474, wR ref(F 2) = 0.1143, T = 293 K.

C26H22N2O4, triclinic P1̅, a = 8.035(3) Å, b = 10.387(4) Å, c = 13.126(5) Å, α = 83.831(10)°, β = 78.214(10)°, γ = 81.470(10)°, Z = 2, V = 1101.78(19) Å3, R gt(F) = 0.0663, wR ref(F 2) = 0.1830, T = 296(2) K.

C40H38CuN4O6, monoclinic, P21/c (no. 14), a = 10.590(4) Å, b = 7.273(3) Å, c = 23.345(9) Å, β = 102.347(7)°, Z = 2, V = 1756.5(12) Å3, R gt(F) = 0.0682, wR ref(F 2) = 0.2373, T = 296 K.

Three polyhydroxyl-bridged tetranuclear MnIII complexes [Mn4(L1a)2(&mu, 3-OMe)2(&mu, 2-OMe)2(MeOH)2] (1), [Mn4(L2a)2(&mu, 2-OMe)2(H2O)2] (2), and [Mn4(L3a)2(&mu, 2-OMe)2(H2O)2] (3) derived from Mnn+-promoted reactivity of Schiff base ligands (HL1 = 1-(4-{[(E)-3,5-dichlorine-2-hydroxybenzylidene]amino}phenyl)ethanone O-benzyloxime, HL2 = 1-(4-{[(E)-3-bromine-5-chloro-2-hydroxybenzylidene]amino}phenyl) ethanone O-benzyloxime, and HL3 = 1-(4-{[(E)-3,5-dibromine-2-hydroxybenzylidene]amino}phenyl)ethanone O-benzyloxime) have been synthesized and characterized. In the MnIII complexes 1, 2, and 3, the newly formed ligands (L1a)4&minus, (L2a)4&minus, and (L3a)4&minus, are derived from the chemoselective cleavage of the C=N bond in the original Schiff base ligands HL1, HL2, and HL3 to form corresponding halogenated salicylaldehyde, 3,5-dichlorosalicylaldehyde, 3-bromine-5-chlorosalicylaldehyde, and 3,5-dibrominesalicylaldehyde, respectively. Then, the further addition of acetone to two halogenated salicylaldehyde molecules in situ &alpha, &alpha, double aldol reaction promoted by Mnn+ ions in the presence of base to give the new ligands ((Lna)4&minus, X-ray crystallographic analyses of the MnIII complexes 1, 2, and 3 show that the three complexes are all tetranuclear structure and crystallizes in the triclinic system, space group P-1. The four MnIII ions and bridging alkoxido groups are arranged in a face-shared dicubane-like core with two missing vertices. In the three MnIII complexes, the asymmetric unit contains two kinds of different MnIII ions (Mn1 and Mn2), where the MnIII ions are all hexacoordinated with slightly distorted octahedral geometries. Simultaneously in the synthesis of multinuclear Mnn+ complexes above, we explored the crystal structure, spatial configuration, and spectroscopic properties of the multinuclear MnIII complexes with different halogen substituents.

Solvent-induced trinuclear NiII complexes, [{Ni(L)(MeOH)}2(OAc)2Ni]·2MeOH (1), [{Ni(L)(EtOH)}2(OAc)2Ni]·2H2O (2), [{Ni(L)(n-PrOH)}2(OAc)2Ni]·2H2O (3) and [{Ni(L)(i-PrOH)}2(OAc)2Ni] (4), have been prepared with an unsymmetric Salamo-like ligand H2L, and characterized via X-ray crystallography, FT-IR, UV-Vis and fluorescence spectra. In complexes 1, 2, 3 and 4, there are two ligand (L)2− moieties, two acetato ligands, two coordinated methanol, ethanol, n-propanol or i-propanol molecules, respectively, as well as other crystallizing solvent molecules. Two acetato ligands coordinated to the three NiII ions via usual Ni-O-C-O-Ni bridges, and four µ-phenoxo oxygen atoms coming from two [NiL(solvent)] units coordinate to the central NiII ions. Although different solvents are induced in the complexes, all the NiII ions are six-coordinated and adopt geometries of distorted octahedron. Magnetic measurements were performed on complex 2, an intramolecular antiferromagnetic interaction was observed between NiII ions and a simulation of the experimental data gives J = −2.96 cm−1 and g = 2.30.

A new Cu(II) complex with asymmetric Salamo-type ligand (H2L, 4-bromo-6′-ethoxy-2,2′-[ethylenedioxybis(nitrilomethylidyne)]diphenol) has been synthesized and characterized structurally. The X-ray crystal structure of the Cu(II) complex shows it to be a binuclear complex, in which each Cu(II) atom is in a distorted square-pyramidal geometry. The Cu(II) complex crystallizes in the monoclinic system, space group P21/c, with unit cell parameters a = 14.7109(1), b = 8.6254(7), c = 30.124(3) A, β = 100.7400(1), and Z = 4. The Cu(II) complex consists of two Cu(II) atoms, and two L2– units, and each Cu(II) complex molecule links four other molecules into an infinite 2D-layer supramolecular structure. Meanwhile, the Cu(II) complex exhibits emission with the maximum emission wavelength λmax = 443 nm when excited at λex = 340 nm.

Two new Co(II) complexes, [{Co(L)}2{Co(Pic)2(CH3OH)2}] (1) and [{CoL(μ-OAc)}2Co] (2), where H2L = 2,2′-[Ethylenedioxybis(nitrilomethylidyne)]dinaphthol, were designed, synthesized and characterized by elemental analysis, FT-IR spectra, UV-Vis spectra, and X-ray crystallography. Complex 1 consists of two [CoL] and one [Co(Pic)2(CH3OH)2] (Pic = picrate) units and in the [CoL] unit, the Co(II) atom is tetra-coordinated with a slightly distorted square-planar geometry. In the [Co(Pic)2(CH3OH)2] unit, the Co(II) atom is hexa-coordinated with a slightly distorted octahedral geometry. Meanwhile in complex 2, two acetate ions coordinate to three Co(II) atoms through Co-O-C-O-Co bridges and four μ-naphthoxo oxygen atoms from two [CoL] units also coordinated to the central Co(II) atom. Thus, complex 2 has two distorted square pyramidal coordination geometries around the terminal Co(II) atom and an octahedral geometry around the central Co(II) atom. The supramolecular structures of complex 1 is a 3D-network supramolecular structure linked by C-H···O hydrogen bonds and π···π stacking interaction, but complex 2 possesses a self-assembled 2D-layer supramolecular structure linked by C-H···π and π···π stacking interactions. The structure determinations show that the coordination anions are important factors influencing the crystalline array.

[Zn4(L1)2(OAc)2(CH3CH2OH)2] and [CuL2(H2O)] with new asymmetric Salamo-type ligands have been synthesized and characterized. There are two coordination geometries (trigonal bipyramidal and square pyramidal) in the Zn(ΙΙ) complex, and the Cu(II) complex has square-pyramidal geometry. A self-assembling continual zigzag chain is formed by intermolecular hydrogen bonds in the Cu(II) complex. The self-assembling array of the Zn(II) complex is linked by intermolecular C–H⋯O and C–H⋯π interactions. Blue emissions of the Zn(II) and Cu(II) complexes in DMF solution are exhibited by fluorescence.

A new mononuclear CdII complex, [CdL(H2O)2], with halogen-substituted Salen-type bisoxime ligand (H2L = 4,4′-dibromo- 6,6′-dichloro-2,2′-[ethylenedioxybis(nitrilomethylidyne)]diphenol), was synthesized and structurally characterized. The CdII complex crystallizes in the monoclinic system, space group C2/c. The CdII center exhibits a slightly distorted octahedral geometry with halogen-substituted Salen-type bisoxime ligand forming the basal N2O2 coordination plane and two oxygen atoms from the coordinated water molecules in the axial position. An infinite 1D metal-water chain is formed by intermolecular hydrogen-bonding and π-π stacking interactions of neighboring benzene rings. Supplemental materials are available for this article. Go to the publisher's online edition of Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistry to view the supplemental file.

A new trinuclear Ni(II) complex {[NiL(DMF)]2(OAc)2Ni}·2DMF (H2L = 4,4′-dichloro-2,2′-[(1,3-propylene)dioxybis(nitrilomethylidyne)]diphenol) is synthesized and characterized by elemental analyses, IR spectra, UV-Vis spectra and X-ray crystallography. The results show that the Ni(II) complex consists of three Ni(II) ions, two tetradentate (μ-L)2− units, two coordinated μ-acetate ions, two coordinated DMF molecules, and two crystallization DMF molecules. All hexacoordinated Ni(II) ions of the complex have a slightly distorted octahedral geometry. The crystal packing of the Ni(II) complex reveals a notable feature of this structure: the formation of an infinite supramolecular 2D layered structure by virtue of intermolecular C-H…O hydrogen bonding.

A new Cu(II) complex, [Cu(L)2], has been synthesized via the complexation of copper(II) acetate monohydrate with a new oxime-type ligand (HL = 1-(3-{[(E)-3-bromo-5-chloro-2-hydroxybenzylidene]amino}phenyl)ethanone oxime). X-ray crystallographic analysis reveals that the complex is a mononuclear complex. The Cu(II) atom is four-coordinated by the phenolate O atoms and imine N atoms from two oxime-type ligands, in a square-planar geometry in which the dihedral angle of two coordination plane (Cu1N1O1 and Cu1N#1O#1) is 0°. The crystal packing of the Cu(II) complex shows that a notable feature of this structure resides in the formation of a novel 3D supramolecular networks through intermolecular O–H···N, C–H···O, and C–H···π interactions. Supplemental materials are available for this article. Go to the publisher's online edition of Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistry to view the supplemental file.

A supramolecular CoII complex, [CoL(H2O)2], bearing Salen-type bisoxime chelate ligand 4,4′,6,6′-tetrachloro-2,2′-[ethylenedioxybis(nitrilomethylidyne)]diphenol (H2L), has been synthesized and structurally characterized by elemental analyses, IR spectra, UV–vis spectra, and X-ray diffraction techniques. The crystal structure of [CoL(H2O)2] indicates that the CoII complex consists of one CoII atom, one L2– unit, and two coordinated water molecules. The CoII complex exhibits slightly distorted octahedral geometry with the Salen-type bisoxime ligand forming the basal N2O2 coordination plane and two oxygen atoms from the coordinated water molecules in the axial positions. An infinite 1D metal–water chain and 2D supramolecular network structure were formed by intermolecular O-H···O, O-H···Cl, and C-H···O hydrogen bonding and π-π stacking interactions. Supplemental materials are available for this article. Go to the publisher's online edition of Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Met...

A new mononuclear Zn(II) complex, [ZnL(HOAc)] (1) (H2L = 6,6’-diethoxy-2,2’-[1,2-ethylenedioxybis(nitrilomethylidyne)]diphenol), was synthesized by reaction of H2L and Zn(II) acetate under solvothermal conditions. Complex 1 acts as a metallohost possessing a pentadentate O5 donor. Complex 1 molecules bonded to one Sr(II) or Ba(II) form two new hetero-trinuclear complexes, [(ZnL)2M(OAc)2] (M = Sr (2), Ba (3)). In 2 and 3, Zn(II) ions are five-coordinate, but the Sr(II) or Ba(II) ion is ten-coordinate by four μ-phenolic oxygens from two L2- units, four oxygens from four ethoxy groups and two oxygens from two μ-acetato ligands. Furthermore, 1, 2 and 3 exhibit blue emissions with the maximum emission wavelengths λmax = 477, 500 and 471 nm when excited at 360 nm.

The tri-nuclear cobalt(II) complex, [(CoL)2(μ-OAc)2Co]·2CHCl3 (H2L = 5,5'-dimethoxy-2,2'-[(ethylene)dioxybis(nitrilome thylidyne)]diphenol), has been synthesised. Its X-ray structure shows it to contain two acetate ions coordinating to the three cobalt(II) atoms through Co–O–C–O–Co bridges, and four μ-phenoxo-oxygen atoms from two [CoL] chelates also coordinating to the central cobalt(II) atom. The complex possesses two penta- and one hexa-coordinated cobalt atoms. The crystal packing of the CoII complex shows that a 2D-layer supramolecular network parallel to the ab-plane is formed through intermolecular C–H···O and C–H···Cl hydrogen bonding interactions.

Two nickel(II) complexes, namely {[NiL(MeOH)(μ-OAc)]2Ni}·2CH2Cl2·2MeOH (1) and {[NiL(EtOH)(μ-OAc)]2Ni}·2EtOH (2) {H2L = 5, 5′-dimethoxy-2, 2′-[(ethylene)dioxybis(nitrilomethylidyne)]diphenol}, were synthesized and structurally characterized. Two trinuclear NiII complexes are both hexacoordinate around the central NiII atoms, showing octahedral coordination arrangements, and each complex comprises three divalent NiII atoms, two deprotonated L2– ligands, in which four μ-phenoxo oxygen atoms forming two [NiL(X)] (X = MeOH or EtOH) units, and coordinated and non-coordinated solvent molecules. Complex 1 exhibits a 2D supramolecular network through intermolecular O–H···O, C–H···O and C–H···π interactions, whereas complex 2 forms an infinite 1D chain by intermolecular C–H···O hydrogen bonding interactions.

Salen-type bisoxime 5,5′-dimethoxy-2,2′-[(ethylenedioxy)bis(nitrilomethylidyne)]diphenol (H2L) and its trinuclear Ni(II) cluster {[(NiL)(n-BuOH)]2(μ-OAc)2Ni} · n-BuOH have been synthesized and structurally characterized. The structure of H2L adopts an L-shape conformation where the two salicylaldoxime moieties are well separated. In the trinuclear Ni(II) cluster, two acetates coordinate to three Ni(II)'s through Ni–O–C–O–Ni bridges, four μ-phenoxos from two [NiL(n-BuOH)] units also coordinate to Ni(II), and two n-butanols coordinate to two terminal Ni(II)'s forming a distorted octahedral geometry. The Ni–O–C–O–Ni and μ-phenoxo bridges play important roles in assembling Ni(II) and the ligands. H2L forms a rectangle-like large cave structure through O–H ··· N, C–H ··· O, and C–H ··· π hydrogen-bond interactions, whereas its trinuclear Ni(II) cluster exhibits a 3-D supramolecular network structure through intermolecular O–H ··· O, C–H ··· O, and C–H ··· π hydrogen-bond interactions.

A new Salen-type bisoxime chelating ligand, 3,3′-dimethoxy-2,2′-[(1,3-propylene)dioxybis(nitrilomethylidyne)]diphenol (H2L), and its Ni(II) cluster, [{NiL(CH3CH2OH)}2(OAc)2Ni]·2CH3CH2 OH·CH3COCH3, have been synthesized and characterized by elemental analyses, FT-IR spectra, UV-vis spectra, 1H-NMR, molar conductance measurements, and thermal properties. X-ray crystallographic analyses reveal that the structure of the Ni(II) cluster is as follows: two acetate groups coordinating to three metal(II) ions through Ni–O–C–O–Ni bridges and four μ-phenoxo oxygen atoms from two [NiL(CH3CH2OH)] units also coordinating to metal(II) ions. In the cluster, two ethanol molecules coordinate to the two terminal nickel(II) ions and form a trinuclear structure. Meanwhile, the Ni–O–C–O–Ni and μ-phenoxo bridges play important roles in assembling metal ions and ligands.

An unexpected dinuclear Cu(II) complex, [Cu2(L2)2] (H2L2 = 3-methoxysalicylaldehyde O-(2-hydroxyethyl)oxime), has been synthesized via complexation of Cu(II) acetate monohydrate with H4L1. Catalysis by Cu(II) results in unexpected cleavage of two N–O bonds in H4L1, giving a dialkoxo-bridged dinuclear Cu(II) complex possessing a Cu–O–Cu–O four-membered ring core instead of the usual bis(salen)-type tetraoxime Cu3–N4O4 complex. Every complex links six other molecules into an infinite-layered supramolecular structure via 12 intermolecular C–H ··· O hydrogen bonds. Furthermore, Cu(II) complex exhibits purple emission with maximum emission wavelength λmax = 417 nm when excited with 312 nm.

An unprecedented dinuclear copper(II) complex, [Cu2(L2)2] (H2L2 = 3-Methoxysalicylaldehyde O-(2-hydroxyethyl)oxime), has been synthesized via the complexation of copper(II) acetate monohydrate with unsymmetrical Salen-type ligand H2L1 (H2L1 = 3-Methoxy-2,2′-[ethylenedioxybis(nitrilomethylidyne)]diphenol). The crystal structure of the copper(II) complex has been determined by single-crystal X-ray diffraction method. The catalysis of copper(II) ions results in the unexpected cleavage of one of the N˭O bonds in the ligand H2L1, giving a novel dialkoxo-bridged dinuclear copper(II) complex possessing a Cu˭O˭Cu˭O four-membered ring core instead of the usually desired Salen-type bisoxime Cu˭N2O2 mononuclear complex.

A tetranuclear Zn(ΙΙ) complex, [Zn4L2(OAc)2(CH3OH)2] with an unsymmetric Salen-type bisoxime (H3L = 6-hydroxy-4′,6′-dibromo-2,2′-[ethylenediyldioxybis(nitrilomethylidyne)]diphenol), has been synthesized and structurally characterized. There are two kinds of coordination geometry (trigonal bipyramidal and square pyramidal) in the Zn(ΙΙ) complex. The molecule has serious distortion probably from the asymmetry. The complex exhibits blue emission with the maximum emission wavelength λ max = 423 nm when excited with 340 nm.

Two solvent-induced complexes, [CoL2(CH3OH)2] (1) and [CoL2(CH3CH2OH)2] (2), have been synthesized by the reaction of an oxime-type ligand (HL, 4-[(Ethoxyimino)(phenyl)methyl]-5-methyl-2-phenyl-1H-pyrazol-3(2H)-one) with cobalt(II) acetate tetrahydrate in different solvents. X-ray crystallographic analyses have indicated that complexes 1 and 2 have a similar structure, consisting of one CoII atom, two L− units, and two coordinated methanol or ethanol molecules. Interestingly, two CoII atoms in the structures of complexes 1 and 2 are all six-coordinated, approaching a staved octahedral geometry, but complexes 1 and 2 are grown up in methanol/chloroform and ethanol, respectively. Right because of this, solvent effect cause to the difference of the crystal structures: complex 1 forms an infinite supramolecular chain by intermolecular hydrogen bonds, while complex 2 exhibits three-dimensional supramolecular networks through intermolecular hydrogen bonds and C-H···π interactions.

A dinuclear Cu(II) complex, [Cu2(L2)2] (H2L2 = 4-methoxysalicylaldehyde O-(2-hydroxyethyl)- oxime), has been synthesized through the complexation of Cu(II) acetate monohydrate with the ligand H2L1 (H2L1 = 5,5´ -dimethoxy-2,2´-[(ethylene)dioxybis(nitrilomethylidyne)]diphenol), and characterized by elemental analyses, IR, UV/Vis and emission spectra. The crystal structure of the Cu(II) complex has been determined by single-crystal X-ray diffraction. The catalysis by Cu(II) ions results in the unexpected cleavage of the N-O bonds in the ligand H2L1, giving a novel dialkoxo-bridged dinuclear Cu(II) complex possessing a Cu-O-Cu-O four-membered ring core instead of the expected salen-type bisoxime Cu-N2O2 complex

A new dinuclear CuII complex, [Cu2(3-MeOSalamo-2)(H2O)3]·2pic·CH3COCH3·H2O, has been synthesized by the reaction of copper(II) picrate tetrahydrate with H2(3-MeOSalamo-n) (n = 2). X-ray crystallographic analysis reveals that the complex is a dinuclear structure when the O-alkyl chain length is relatively short (two CH2 groups), while a tetranuclear structure is obtained when the O-alkyl chain length becomes longer (four CH2 groups). In the complex, the μ-phenoxo bridging, picratol, and intermolecular hydrogen bonds play important roles in assembling CuII ions and ligands. Interestingly, the complex not only has a helical chain, but has an infinite metal–water chain supramolecular structure.

Three mononuclear Schiff base copper(II) complexes, [Cu(L1)2] (1), [Cu(L2)2] (2) and [Cu(L3)2] (3) (HL1= 2,4-dichloro-6-[(2-chloro-3-pyridyl)iminomethyl]phenol, HL2 = 2,4-dibromo-6-[(2-chloro-3-pyridyl)-iminomethyl]phenol, HL3 = 2-bromo-4-chloro-6-[(2-chloro-3-pyridyl)iminomethyl]phenol), have been synthesized and characterized by elemental analyses, IR, UV–Vis spectra, and X-ray single crystal diffraction. X-ray structures reveal each crystal unit contains two molecules and the coordination environment around the copper(II) atom is tetracoordinated by two Schiff base ligands, showing a tetrahedron geometry with some distortion. Pairs of intermolecular C–H···X (X = Cl or Br), C–H···N and C–H···O hydrogen bonds form many hydrogen bonding rings and play a crucial role in stabilizing the crystal structures.

A new Co(II) cluster, {[CoL(DMF)]2(OAc)2Co}·2DMF (H2L = 4,4′-dichloro-2,2′-[(1,3-propylene)dioxybis (nitrilomethylidyne)]diphenol), has been synthesized and characterized by elemental analysis, IR spectrum, UV–Vis spectrum, and X-ray diffraction method. The results indicate that the Co(II) cluster consists of three Co(II) ions, two tetradentate (μ-L) 2− units, two coordinated μ-acetate ions, two coordinated DMF, and two crystallizing DMF molecules. All the hexa-coordinated Co(II) ions of the Co(II) cluster have a slightly distorted octahedral geometry. The crystal packing of the Co(II) cluster shows that a notable feature of this structure resides in the formation of a novel 2D supramolecular structure through intermolecular C‒H···O interaction and weak intramolecular C‒H···(Ph) interaction along the b-axes.

Two new uranyl-organic coordination compounds, UO2(NDC)[(CH3)2SO)]2 ( 1 ) and [UO2(NDC)(CH2OH)2] ( 2 ) (H2NDC = 1,4-naphthalene dicarboxylate), have been synthesized from the solutions of dimethyl sulfoxide (DMSO) and ethylene glycol (EG), respectively, through a volatilization method. Single-crystal X-ray diffraction analyses show that compound 1 consists of novel straight chains modified by pairs of DMSO molecules, whereas compound 2 features one-dimensional zigzag chains which are cross-linked by non-coordinating solvent molecules through hydrogen bonding interactions, forming a two-dimensional network. Both 1 and 2 decompose rhodamine B (RhB) molecules efficiently under the irradiation of UV and visible light.

Two new complexes, [Cu(L1)2] (1) and [Cu(L2)2(H2O)]·CH3OH (2), have been synthesized via the complexation of copper(II) acetate monohydrate with two mono-oxime chelating ligands (HL1: 4-[(Methoxyimino)(phenyl)methyl]-5-methyl-2-phenyl-1H- pyrazol-3(2H)-one and HL2: 4-[(Ethoxyimino)(phenyl)methyl]-5-methyl-2-phenyl-1H-pyrazol-3(2H)-one), respectively. X-ray crystal structure determination of the two complexes show that complex 1 consists of one copper(II) ion, two bidentate (L1)− units, and the copper atom of complex 1 has a square planar geometry distorted tetrahedrally with four-coordination, while complex 2 consists of one copper(II) ion, two bidentate (L2)− units, one coordinated H2O, and one crystallizing methanol molecule, as expected from the analytical data. And the copper atom of complex 2 has a slightly distorted tetragonal pyramid geometry with five-coordination. Complex 2 is a self-assembling infinite chain supramolecular structure formed by intermolecular hydrogen bonds. Meanwhile, the photoph...

Two CoII complexes, namely {[CoL(MeOH)(μ-OAc)]2Co}·2MeCN·2MeOH (1) and {[CoL(EtOH)(μ-OAc)]2Co}·3EtOH (2) (H2L=3,3′-dimethoxy-2,2′-[(1,3-propylene)dioxybis(nitrilomethylidyne)]diphenol), have been synthesized and characterized by X-ray crystallography. Both complexes contain octahedral coordination geometries, comprising three CoII atoms, two deprotonated bisoxime L2− units in which four μ-phenoxo oxygen atoms form two [CoL(X)] (X = MeOH or EtOH) units, two acetate ligands coordinated to three CoII centers through Co–O–C–O–Co bridges, and coordinated and non-coordinated solvent. Both complexes exhibit 2D supramolecular networks through different intermolecular hydrogen-bonding interactions.

Two solvent-induced trinuclear nickel(II) clusters, [{NiL(CH(3)OH)}(2)(OAc)(2)Ni].2CH(3)OH (I) and [{NiL(C(2)H(5)OH)}(2)(OAc)(2)Ni].2C(2)H(5)OH (II), have been synthesized by the reaction of a new Salen-type bisoxime chelating ligand of 5,5'-di(N,N'-diethylamino)-2,2'-[(1,3-propylene)dioxybis(nitrilomethylidyne)]diphenol (H(2)L) with nickel(II) acetate tetrahydrate in different solvents. Clusters I and II were characterized by elemental analyses, IR spectra, UV-vis absorption spectra, TG-DTA and X-ray diffraction methods. In clusters I (or II), there are two ligand moieties (which provide N(2)O(2) donors), two acetate ions, two coordinated methanol (or ethanol) molecules and two crystallizing methanol (or ethanol) molecules, which result in the formation of three slightly distorted octahedral geometries around Ni(II) ions. Interestingly, nickel(II) ions in the structures of clusters I and II are all six-coordinated geometry, but clusters I and II are grown up in different solvent. Right because of this, solvent effect cause to their different crystal structures.

Three new supramolecular complexes, [Cu(L1)H2O]n (1), [Zn(L2)(H2O)2]n (2), and [Cd(L2)(H2O)2]n (3), have been synthesized and characterized by FT-IR spectra, fluorescence spectra, and thermal analyses. And the structures of complexes 1–3 have been elucidated by X-ray analyses. Complex 1 is square pyramidal geometry with an unusually long bond (2.262 A) from penta-coodinated CuII center to the oxygen atom of the apical coordinated water molecule. Molecules are linked by hydrogen bonding between the coordinated water and the phenolic oxygen atoms of adjacent molecules, thus formed a self-assembling continual zigzag chain supramolecular structure. The crystal structure of complex 2 (or 3) has indicated that the complex consists of one ZnII (or CdII) atom, one L2− unit and two coordinated water molecules, the coordination number of the ZnII (or CdII) atom is six, and formed an infinite metal–water chain supramolecular structure by intermolecular hydrogen bonds and π–π stacking of neighboring benzene rings. Meanwhile, the thermal and photophysical properties of the resulted complexes have also been discussed.