Synthesis and Structure of a New Coordination Polymer [Cd(pzdc)(bpy)]<Subscript>n</Subscript> (H<Subscript>2</Subscript>pzdc = Pyrazine-2,3-dicarboxylic Acid,bpy = 2,2′-Bipyridine)

Abstract A new 3D coordination polymer, [Cd(pzdc)(bpy)]_n (1) (pzdc = pyrazine-2,3-dicarboxylic acid, bpy = 2,2′-bipyridine), has been hydrothermally synthesized and characterized by the elemental analyses, IR spectrum and single crystal X-ray diffraction. X-ray diffraction analysis reveals that 1 (C₁₆H₁₀CdN₄O₄) crystallizes in monoclinic space group P2₁/c, features an interesting 3D zipper-like networks constructed by 2D layers via strong π–π packing interactions. Cell unit parameter for 1: a = 9.767(1), b = 14.022(2), c = 13.719(2) ?, β = 100.86(1)^o, and Z = 4. Graphical Abstract A new 3D coordination polymer, [Cd(pzdc)(bpy)]_n (pzdc = pyrazine-2,3-dicarboxylic acid, bpy = 2,2′-bipyridine), has been hydrothermally synthesized and characterized by the elemental analyses, IR spectrum and single crystal X-ray diffraction. X-ray diffraction analysis reveals that [Cd(pzdc)(bpy)]_n features an interesting 3D zipper-like networks constructed by 2D layers via strong π–π packing interactions.      

Synthesis,Characterization and Fluorescent Property of Two Mixed Ligand Coordination Polymers Constructed from 4-Cyclohexene-1,2-dicarboxylate and Nitrogen-Containing Ligands

Abstract  

Two new coordination polymers [Cd(1,2′-cy)(btx)_0.5H₂O]_n 1 and {[Ni(1,2-cy)(2,2′-bipy)(H₂O)₂]·3H₂O}_n 2 (1,2′-cy=4-cyclohexene-1,2-dicarboxylate, btx=1,4-bis(triazol-1-ylmethyl)benzene, 2,2′-bipy=2,2′-bipyridine) had been synthesized. Their structures were characterized by elemental analysis, IR, TG and X-ray single-crystal diffraction analysis. Crystal data for complex 1: Triclinic, space group P-1, a = 6.4303(13) ?, b = 10.399(2) ?, c = 11.713(2), α = 83.04(3)°, β = 81.87(3)°, γ = 83.84(3)°, and Z = 2. For complex 2: Orthorhombic, space group Pbcn, a = 15.613(3) ?, b = 13.970(3) ?, c = 21.290(4) ?, and Z = 4. Complex 1 exhibits an interesting two-dimensional wavelike covalent layer structure. When Ni salt was replaced by Cd salt, and reacts with 1,2′-cy and 2,2′-bipy, one-dimensional chain-like complex 2 was obtained. Furthermore, the fluorescent property of complex 1 was reported.     

Synthesis,crystal structure,thermal behavior and luminescence property of a cobalt(II) complex of pyridine-2,6-dicarboxylic acid containing benzimidazole as auxiliary ligand

The new cobalt(II) complex [Co(pydca)(bim)₃] (1) (where H₂pydca = pyridine-2,6-dicarboxylic, bim = benzimidazole) has been synthesized and characterized by elemental analysis, Infrared spectroscopy, X-ray single crystal analysis, thermogravimetric and fluorescent analysis. Single crystal X-ray diffraction analysis reveals that the mononuclear complexes are linked by N–H…O hydrogen bonds. Fluorescent analysis reveals that complex 1 exhibits intense luminescence in ethanol solution at room temperature.     

Structural Investigation of Metal-Organic Cu(II) Coordination Frameworks Constructed from N-donor and α, ω-Dicarboxylate Ligands by One Pot Synthesis: Zigzag Strands,Layered Networks and Its Interaction with Lattice Water Molecules

Abstract  

Two metal organic frameworks involving α, ω-dicarboxylates and 2,2′-bpy, [Cu(2,2Bpy)(μ-adipate-H2)] _n ·2·H₂O 1 and [Cu₂ (2,2′-bpy)₂(μ-adipate-H)₂(μ-adipate-H2)]·3H₂O 2 have been synthesized by one pot reaction and structurally characterized. Pentacoordinated Cu(II) zigzag polymeric chain of 1 is composed of linking the adjacent Cu(2,2′-bpy)(H₂O) units through terminal craboxylate oxygens of two different adipate dianion in cis coordination pattern with the metal center. Both the Complexes were crystallized in triclinic system, P-1 space group with cell parameters a = 6.8948(5), b = 10.7098(7), c = 12.4332(8) ?; α = 82.1120(10), β = 80.4950(10), γ = 72.9560(10)°, V = 861.87(10) ?³ for 1, a = 9.5058(6), b = 9.9341(7), c = 12.6460(8) ?; α = 70.5080(10), β = 73.5740(10), γ = 75.0720(10)°, V = 1062.05(12) ?³ for 2 respectively. Extensive hydrogen bonding interaction is observed between the lattice water molecules and the coordination network. Compound 2 is a layered architecture, where the neutral framework is constructed by two different adipate anions (in monoanionic and dianionic form) coordinating to the metal center. Interestingly, three water molecules present in the lattice of compound 2 are involved in hydrogen bonding network among themselves, creating a centro-symmetric hexameric water cluster composed of a tetracyclic ring with dangling water molecules attached at alternate positions of the rectangle, which interact with the carboxylate oxygen, thereby extending the hydrogen bonded water network.     

Two d10 Coordination Complexes Based on the Substitutional Aromatic Multicarboxylate and N-Donor Co-Ligands: Syntheses,Structures, and Properties

Two new coordination complexes, formulated as [Cd₂(3-NPA)(phen)₄(H₂O)₂]₂ (1) and [Zn(3-NPA)(phen)(H₂O)]_n (2) (3-NPAH₂ = 3-nitrophthalic acid, phen = 1,10-phenanthroline) have been synthesized by hydrothermal reactions of the rigid neutral ligand phen with metal ions in the presence of 3-NPAH. X-ray analysis shows that complex 1 is a 0D dinuclear structure that is arranged to form a 3D supramolecular framework through hydrogen bonds and π–π stacking interactions. In polymer 2, the 3-NPA^2? anions coordinate the Cd(II) ions in a tridentate mode to form a 1D infinite chain structure, which is connected by the hydrogen bonds and π–π stacking interactions resulting in a 3D supramolecular architecture. In addition, the two complexes were characterized by infrared spectroscopy, elemental analysis, luminescent properties, thermo gravimetric analysis, and powder X-ray diffraction (PXRD).     

Magnetic properties and sensitized visible and NIR luminescence of DyIII and EuIII coordination polymers by energy transfer antenna ligands

Two coordination polymers, {[Ln(2-stp)(4,4′-bipy)(H₂O)].(H₂O)}, [Ln = Dy (1) and Eu (2), 2-stp = 2-sulfoterephthalate and 4,4′-bipy = 4,4′-bipyridine] have been characterized by solid state UV-vis, FTIR spectra, X-ray single crystal diffraction and solid state photoluminescence. Variable-temperature magnetic susceptibility and isothermal magnetization as function of external magnetic field is also studied for both complexes. After ligand-mediated excitation, both complexes show the characteristic visible and NIR luminescence of the corresponding Ln^III ions (Ln = Dy, Eu) which is due to efficient energy transfer from the ligands to the central Ln^III ions via an antenna effect. The indirect energy transfer in both complexes has been investigated and discussed in detail.     

Synthesis and crystal structure of trans-tetrachloro(C, C-dichloro-C-phenyl-methyl-nitrido)(phenylnitrilo)tungsten(VI), trans-[WCl4(NCCl2Ph)(NCPh)]

A product of the insertion, namely, trans-tetrachloro(C, C-dichloro-C-phenyl-methyl-nitrido)(phenylnitrilo) tungsten(VI), trans-[WCl₄(NCCl₂ Ph)(NCPh)] (I), is synthesized by the reaction of WCl₆ with PhCN in CCl₄ under refluxing for 2 h. Judging from the characteristic IR bands ν(C≡N) and ν(W≡N), the complex synthesized is identical to the compound prepared earlier at room temperature. The crystal structure of complex I is determined using X-ray diffraction analysis. It is revealed for the first time that the coordination polyhedron of the tungsten atom in complex I is a distorted octahedron with four chlorine atoms in the equatorial plane. The axial positions are occupied by the N(1) atom [W-N(1), 2.265(13) Å] of the coordinated benzonitrile group and the N(2) atom [W-N(2), 1.732(13) Å] of the multiply bonded ligand NCCl₂ Ph. __________ Translated from Kristallografiya, Vol. 49, No. 4, 2004, pp. 728–731. Original Russian Text Copyright ? 2004 by Sinyakov, Aleksandrov, Ovchinnikova.     

Syntheses and Crystal Structures of Two New Cadmium(II) and Nickel(II) Complexes with 1,4-Phenylenediacetate and 2,2′-Bipyridyl-Like Ligands

Abstract  

Two new complexes, namely [Cd(PDA)_0.5(2,2′-bpy)Cl](H₂PDA) (1) and [Ni(PDA)(phen)(H₂O)]₂ (2) (H₂PDA = 1,4-phenylenediacetic acid, 2,2′-bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline), have been synthesized and characterized by elemental analysis, IR spectra and X-ray crystal diffraction. Single-crystal X-ray diffraction analysis shows that complex 1 crystallizes in the triclinic space group P-1 with unit cell dimensions a = 8.760 (4) ?, b = 11.190 (5) ?, c = 13.917 (7) ?, α = 110.383 (5)°, β = 101.736 (5)°, γ = 100.612 (5)°, V = 1202.8 (10) ?³, Z = 2, R ₁ = 0.0314 and wR ₂ = 0.0898. Complex 2 crystallizes in the monoclinic space group P2(1)/n with unit cell dimensions a = 9.911 (3) ?, b = 17.924 (6) ?, c = 10.638 (4) ?, β = 94.998 (5)°, V = 1882.7 (11) ?³, Z = 2, R ₁ = 0.0397 and wR ₂ = 0.1150. In complex 1, Cd(II) ions are alternately bridged by PDA ligands and chloride ions into 1D chains and the PDA ligands display trans-configuration. Complex 2 is a dimer and two Ni(II) ions are linked by two PDA ligands with cis-configuration, resulting in a cyclic structure. In spite of these differences, both in complexes 1 and 2 there are π–π stacking interactions and hydrogen bonding to make them 3D supramolecular frameworks.     

Synthesis,crystal structure and photophysical studies on a ruthenium(II) carbonyl hydrido compound based on 2,2′‐bipyridyl‐5,5′‐dicarboxylic acid (H2bpdc)

A novel complex, namely [Ru^II(PPh₃)(CO)(H)(Hbpdc)]·2MeOH ( 1 ) (H₂bpdc = 2,2′‐bipyridyl‐5,5′‐dicarboxylic acid), has been synthesized from the reaction of H₂bpdc with [Ru^II(PPh₃)₃(CO)(H)₂] in methanol under mild condition and characterized by elemental analysis, IR spectrum, ESI mass spectrometry, and single crystal X‐ray diffraction. The structure shows that the complex crystallizes in the monoclinic space group P2₁/c with unit cell parameters a = 11.8984(13) Å, b = 16.5180(18) Å, c = 25.5322(19) Å, β = 115.302(4)°, V = 4536.6(8) ų, Z = 4. This compound features a 1‐D supramolecular chain constructed via hydrogen bonds. Its photophysical properties have been investigated in MeOH solution and in the solid state at room temperature.     

Synthesis,Structure and Electrochemical Property of a New Copper(II) Complex Based on Benzene-1,2,4,5-tetracarboxylate and 2,5-Bis(3-pyridyl)-1,3,4-oxadiazole Ligands

Abstract  

A new three-dimensional (3-D) supramolecular complex, [Cu₂(btec)(bpo)₂(H₂O)₂]·8H₂O (1), has been synthesized by hydrothermal reaction with the mixed ligands benzene-1,2,4,5-tetracarboxylate (btec) and bent dipyridyl based ligand 2,5-bis(3-pyridyl)-1,3,4-oxadiazole (bpo), and structurally characterized by elemental analysis, IR, TG, powder-XRD and single-crystal X-ray diffraction analysis. The results reveal that each Cu(II) ion is bridged by two different ligands (btec and bpo) to form a 2-D polymer layer in complex 1. The adjacent layers are further linked by 1-D H-bonded water chains simultaneously containing (H₂O)₆ rings and (H₂O)₈ rings to form a 3-D supramolecular framework. Moreover, the electrochemical behavior of complex 1 bulk-modified carbon paste electrode (1-CPE) has been reported.     

The Crystal Structure of [La(NO3)6{Cu(2,2′-bipy)2}2][La(NO3)6Cu(2,2′-bipy)2]CH3CN with the Most Profuse Modes of Nitrate Coordination

The title compound [La(NO₃)₆{Cu(2,2′-bipy)₂}₂][La(NO₃)₆Cu(2,2′-bipy)₂] CH₃CN was synthesized, the crystal and molecular structures were determined at room temperature. The complex formed monoclinic crystals, space group P21/n (No.14), a = 10.354 (3) A, b = 23.440 (9) A, c = 32.817 (9) A, b = 90.39 (2)°, Z = 4. The crystal structure consisted of a discrete [La(NO₃)₆{Cu(2,2′-bipy)₂}₂]⁺ cation and [La(NO₃)₆Cu(2,2′-bipy)₂]^- anion and a non-coordinated CH₃CN molecule. Each La(III) ion was 12-coordinate with twelve oxygen atoms from six chelating nitrate ligands. There were four modes of nitrate coordination and the coordination geometry of all three copper ions was different in the crystal structure.     

Syntheses, Structures, Fluorescence and Magnetic Property of Two Complexes with the Asymmetric dpa Ligand

Abstract  

Two compounds [Zn(Hdpa)₂(2,2′-bipy)]₂ (1) and [Mn(dpa)(4,4′-bipy)] _n (2) (H₂dpa=2,2′-biphenyldicarboxylate, bipy=dipyridine) are synthesized by hydrothermal reactions and structurally characterized by Single crystal X-ray diffraction analyses. Compound 1 is a dual-core molecular structure of two Zn ions in the same coordination environment, we studied the fluorescence of compound 1. Compound 2 is a layer structure based on the one-dimensional chains bridged by 4,4-bipy, it displays weak antiferromagnetic interactions between the inter-chain Mn²⁺ ions.     

Two-dimensional crown ether complex. Synthesis and crystal structure of [Na(N15C5)]<Subscript>2</Subscript>[Cu(mnt)<Subscript>2</Subscript>]

A novel crown ether complex [Na(N15C5)]₂[Cu(mnt)₂] (1) (where N15C5 = 2,3-naphtho-15-crown-5 and mnt = maleonitriledithiolate, [C₂S₂(CN)₂]^2–) was synthesized and characterized by elemental analysis, FT-IR spectra, UV-visible spectra and single crystal X-ray diffraction. Structural analysis reveals that the complex 1 consists of two [Na(N15C5)]⁺ complex cations and one [Cu(mnt)₂]^2– complex anion and the complex molecules are assembled into a novel 2D network by Na–N interactions. In the network, there are 34-member macrocycles formed by four sodium ions of complex cations and four complex anions through Na–N bonds. In each macrocycle, – stacking interactions occurred between two parallel naphthylene moieties of N15C5. It is interesting that the 2D network displays an open-capped wave-like sheet viewed along the crystallographic a axis.     

Nickel(II) and Cobalt(II) Complexes with Symmetrical Four-Dentate Ligands: Crystal Structures,Characterization, and Initial DNA Binding Mechanism Research

Abstract  

Four new nickel(II) and cobalt(II) complexes of Schiff base ligands: [Ni(L)Cl₂]·2H₂O (I), [Ni(L)(H₂O)₂] (NO₃)₂ (II), [Ni(L)(H₂O)₂] (ClO₄)₂ (III), and [Co(L) (H₂O)₂] (NO₃)₂ (IV) (L = 1,3-[bis(pyridine-2-imino)]propane) have been synthesized. The four complexes have been fully characterized by elemental analysis, IR, absorption spectra, emission spectra, and single-crystal X-ray diffraction analysis. The binding of the four complexes to calf thymus DNA (CT DNA) has been investigated by absorption spectra and emission spectra. The results of the two methods indicate that the action mode of complex I with DNA is intercalative mainly, and the action mode of complexes II, III, IV with DNA cannot be concluded, it should be sustained by other experimental measurements.     

Synthesis and Crystal Structure of [Mn(H2O)(tptz)(CH3COO)][N(CN)2] · 2H2O (tptz = 2,4,6-tris-(2-pyridyl)-1,3,5-triazine)

Abstract  The manganese complex [Mn(H₂O)(tptz)(CH₃COO)][N(CN)₂] · 2H₂O 1 (tptz = 2,4,6-tris-(2-pyridyl)-1,3,5-triazine) has been synthesized and structurally characterized by X-ray diffraction, element analysis and IR spectrum. It crystallizes in the monoclinic space group C2/c, a = 14.6898(1) ?, b = 13.4002(9) ?, c = 26.865(2) ?, β = 99.672(3)°, V = 5213.0(7) ?³, Z = 8. The number of coordination around Mn(II) atom is seven; it is coordinated equatorially by three nitrogen atoms from tptz, and two oxygen atoms from acetate, and axially by one nitrogen atom of dicyanamide and one coordinated water molecule. The crystal structure is stabilized through hydrogen bonds. Index Abstract  The title compound, [Mn(H₂O)(tptz)(CH₃COO)][N(CN)₂] · 2H₂O was synthesized by the treatment of 2,4,6-tris(2-pyridyl)-1,3,5-triazine (tptz) and Mn(OAc)₂ · 4H₂O, with NaN(CN)₂ and its crystal structure determined. Single crystal X-ray diffraction analysis reveals that the number of coordination around Mn(II) atom is seven.      

Structural and Spectroscopic Study of Cu(II) Pyridine-2,6-dicarboxylate Complex with 2-Ethylimidazole

Abstract  

A mononuclear copper(II) complex, [Cu(pydca)(2-Etlm)(H₂O)] (1) (H₂pydca = pyridine-2,6-dicarboxylic acid, 2-Etlm = 2-ethylimidazole), has been synthesized and characterized by elemental analyses, IR, UV–Vis, TG-DTA and single crystal X-ray diffraction. The complex 1 is in the orthorhombic crystal system, space group Pbca and Z = 8. The structural analysis indicated that Cu(II) center is five coordinated in a slightly distorted square pyramidal geometry by one N and two O atoms from a 2,6-pyridine dicarboxylate dianion, one N atom from a 2-ethylimidazole ligand, and one O atom from a aqua molecule. This mononuclear motif of 1 is further assembled to 3D supramolecular framework through strong O–H···O and N–H···O hydrogen bonding interactions.     

Construction of Three Novel Coordination Complexes by 3-Nitrophthalic Acid Plus N-Donor Ligands: Synthesis,Structure, and Properties

In order to explore new coordination frameworks with novel designed 3-nitrophthalic acid and N–donor ancillary ligands, three novel coordination complexes, namely, [Co₂(3-NPA)₂(2,2′-bipy)₂(H₂O)₂]?2H₂O (1), [Mn₂(3-NPA)₂(4,4′-bipy)₃(H₂O)₆]?(4,4′-bipy) (2), and [Pb₂O(3-NPA)]_n (3) (where 3-NPAH₂ = 3-nitrophthalic acid, 2,2′-bipy = 2,2′-bipyridine, 4,4′-bipy = 4,4′-bipyridine), have been hydrothermally synthesized. X-ray structure analysis reveals that 1 and 2 are dinuclear structures, while 3 is a two-dimensional (2D) network polymer. And the hydrogen bonds and π–π stacking also play important roles in affecting the final structure where complexes 1-2 have 3D and 2D supramolecular architectures, respectively. These complexes have been characterized by powder X-ray diffractions (PXRD) and thermal gravimetric analyses (TGA). In addition, their photochemical properties have also been investigated.     

Synthesis and characterization of copper(II) hexaazamacrotetracyclic complex with thiocynate ligand

A mononuclear complex [Cu(L)(NCS)](ClO₄) (1) (L = 1,3,10,12,16,19-hexaazatetracyclo [17,3,1, 1^12.16,0^4.9]tetracosane) has been synthesized and structurally characterized by X-ray crystal structure analysis. The crystals are monoclinic P2₁2₁2₁ with a = 9.596(1), b = 11.285(1), c = 22.446(2) Å, V = 2430.7(3) ų, Z = 4. The copper atom is coordinated by two secondary and two tertiary amines of the macrocycle and one nitrogen atom of the thiocynate ligand in a distorted square-pyramidal geometry. The cyclic voltammogram of 1 exhibits two waves of a one-electron transfer corresponding to Cu^II/Cu^III and Cu^II/Cu^I processes.     

Synthesis,Crystal Structure and Luminescent Property of a Ternary Complex [Cd(sfdb)(3-pytpy)]<Subscript>2</Subscript>·2H<Subscript>2</Subscript>O (H<Subscript>2</Subscript>sfdb = 4,4′-Sulfonyldibenzoic Acid, 3-pytpy = 4′-(3-Pyridyl)-2,2′:6′,2″-Terpyridine)

Abstract  

A new ternary complex [Cd(sfdb)(3-pytpy)]₂·2H₂O (H₂sfdb = 4,4′-Sulfonyldibenzoic acid, 3-pytpy = 4′-(3-pyridyl)-2,2′:6′,2″-terpyridine) 1 has been hydrothermally synthesized and characterized by the elemental analysis, IR spectroscopy and single crystal X-ray diffraction. X-ray diffraction analysis reveals that 1 (C₃₄H₂₄CdN₄O₇S) crystallizes in triclinic space group P-1, features an interesting 1D channel-containing supramolecular structure constructed from grid-like dimers via π–π stacking interactions. Unit cell parameters for 1: a = 8.866(2) ?, b = 11.083(3) ?, c = 15.790(4) ?, α = 103.612(4)°, β = 95.044(3)°, γ = 101.083(4)° and Z = 2. The luminescent spectrum shows the emission peak of complex 1 is at 392 nm which is attributed to the intraligand transition.     

Synthesis and Characterization of Nickel(II) Complex of 3,14-Dimethyl-2,6,13,17-Tetraazatricyclo[14,4,01.18,07.12]Docosane Containing Pyrazine-2-Carboxylate Ligand

Abstract  

The reaction of [Ni(L)]Cl₂·2H₂O (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,0^1.18,0^7.12]docosane) with pyrazine-2-carboxylic acid (H-pyc) yields mononuclear nickel(II) complex, [Ni(L)(pyc)₂]·2H₂O (1). This complex has been characterized by X-ray crystallography, electronic absorption and cyclic voltammetry. The crystal structure of 1 exhibits a distorted octahedral geometry with four nitrogen atoms of the macrocycle and two pyrazine-2-carboxylate ligands. It crystallizes in the triclinic system P-1 with a = 9.6643(17), b = 10.116(3), c = 16.99(4) ?, V = 1633(3) ?³, Z = 2. Electronic spectrum of 1 also reveals a high-spin octahedral environment. Cyclic voltammetry of 1 undergoes two waves of a one-electron transfer corresponding to Ni^II/Ni^III and Ni^II/Ni^I processes.