Syntheses,crystal structures,and catalytic activities of three new Cu(II) coordination polymers based on 2-(1H-1,2,4-triazole)-1-acetic acid

Three new coordination polymers, {[Cu(trza)(2,2′-bipy)(H₂O)]?·?(ClO₄)} _n (1), {[Cu(trza)(2,2′-bipy)(H₂O)]?·?(BF₄)} _n (2), and {[Cu(trza)(4,4′-bipy)]?·?(H₂O)?·?(ClO₄)} _n (3) (Htrza?=?2-(1H-1,2,4-triazole)-1-acetic acid), have been synthesized and characterized by single-crystal X-ray diffraction analysis. Both 1 and 2 exhibit 1-D chain structure while 3 displays 2-D layer structure. The catalytic activities of 1 and 3 in the green oxidative coupling of 2,6-dimethylphenol have been investigated.     

Four anthraquinone-1,5-disulfonate-based metal complexes incorporating N-heterocyclic coligands: synthesis,crystal structures,and fluorescence

Four new anthraquinone-1,5-disulfonate (L)-based metal complexes with N,N-bidentate chelating coligands, {[Pb(phen)₂(L)]?·?4H₂O} _n (1), {[Mn₂(2,2′-bipy)₂(H₂O)₆(L)]?·?L?·?6H₂O} (2), [Co(phen)₂(H₂O)(L)] (3), and [Zn(phen)₂(H₂O)(L)] (4) (phen = 1,10-phenanthroline and 2,2′-bipy?=?2,2′-bipyridine), have been hydrothermally synthesized and were structurally characterized by single-crystal X-ray diffraction, elemental analyses, FT-IR spectra, thermogravimetric curves, and solid luminescence spectra. Structural analysis suggests that 1 is a polymeric 1D zigzag chain bridged by dianionic L. In contrast, the other three complexes have discrete centrosymmetric binuclear structure for 2 and isolated isomorphic mononuclear entities for 3 and 4, which are further assembled into 3D supramolecular networks by abundant hydrogen-bonding and/or π–π stacking interactions. Additionally, 2 and 4 exhibit favorable luminescent emissions, suggesting they are potential candidates for light emission materials.     

Syntheses,structural diversity and properties of three coordination polymers built by chlorophenyl imidazole dicarboxylate

Two 2D coordiantion polymers, [Sr(p-ClPhHIDC)(H₂O)]_n (p-ClPhH₃IDC = 2-(4-chlorophenyl)-1H-imidazole-4,5-dicarboxylic acid) (1) and [Cd₃(p-ClPhH₂IDC)₂(p-ClPhHIDC)₂(H₂O)₂]_n (2) and one 3D polymer {[Co₃(p-ClPhHIDC)₃(H₂O)₃]·6H₂O}_n (3) have been prepared successfully under solvothermal conditions and structurally characterised by elemental analyses, IR and XRPD determinations, and have been further analysed by single-crystal X-ray diffraction. Polymer 1 exhibits a graceful 2D grid sheet structure. Polymer 2 can be regarded as a (3,3,4)-coordinated 2D network. Polymer 3 exhibits a 3D motif with 1D open channels and [Co₁₂(p-ClPhHIDC)₉] bihexagonal rings. The coordination features of the newly prepared imidazole dicarboxylate ligand, p-ClPhH₃IDC, have been discussed from both theoretical and experimental aspects. Furthermore, the solid-state photoluminescence and thermal properties of the polymers have also been investigated.     

Two new Pb(II) coordination polymers, [Pb2(μ-4,4′-bipy) (μ-2-sb)2(DMF)] n and {[Pb2(μ-4,4′-bipy) (μ-2-sb)2(H2O)2] · H2O} n (4,4′-bipy = 4,4′-bipyridine and 2-H2sb = 2-sufobenzoic acid)

Two new 2D Pb₂(μ-4,4′-bipy)(μ-2-sb)₂ coordination polymers, [Pb₂(μ-4,4′-bipy)(μ-2-sb)₂(DMF)] _n (1) and {[Pb₂(μ-4,4′-bipy)(μ-2-sb)₂(H₂O)₂] · H₂O} _n (2), have been synthesized, characterized and studied by X-ray crystallography. The structural studies show the Pb atoms to have seven- and eight-coordinate holodirected geometries.     

The construction of two lanthanide coordination polymers based on 5-hydroxyisophthalate and bipyridine

Two lanthanide coordination polymers, [Tm₂·(5-IPA)₄·(2,2′-Hbipy)₂]·3H₂O (1, 5-H₂IPA?=?5-hydroxyisophthalic acid, 2,2′-bipy?=?2,2′-bipyridine) and [Er·(5-HIPA)₃·(4,4′-bipy)₃·(H₂O)₂]·3H₂O (2, 4,4′-bipy?=?4,4′-bipyridine), have formed by hydrothermal synthesis. Complex 1 exhibits a 2-D coordination network containing parallelepiped-shaped voids occupied by guest 2′2-bipy molecules. Complex 2 possesses a 1-D linear chain structure. The 1-D chains are linked by 4,4′-bipy molecules to form a 3-D supramolecular framework. IR spectroscopy, elemental analysis, and thermogravimetric analysis were also investigated.     

A series of new oxo-vanadium(IV) complexes with octahedral coordinated vanadium centers

A series of new oxo-vanadium(IV) complexes, [VOCl0.69(OH)0.31 (2,2′-bipy)2]Cl·2H2O (1, 2,2′-bipy?=?2,2′-bipyridine) [(VO)₂Cl₄(4,4'-bipy)₃ (H₂O)₂] (2, 4,4'-bipy?=?4,4'-bipyridine), [VO(ida)(H₂O)]_n (3, H₂ida?=?iminodiacetic acid), and [(VO)₂(oa)₄]_n·4n(H₃O)·n(H₂O) (4, H₂oa?=?oxalic acid), have been synthesized and structurally characterized. 1 contains a [VOCl_0.69(OH)_0.31(2,2′-bipy)₂]⁺ cation, Cl ^– anion and two free H₂O molecules. 2 exhibits a binuclear centrosymmetric moiety built up from two [VOCl₂(4,4'-bipy)(H₂O)] units and one bridging 4,4'-bipy ligand, which provides a rare example of a 4,4'-bipy molecule acting as monodentate ligand. 3 displays a neutral chain [VO(ida)(H₂O)]_n constructed by the linkages of [VO(H₂O)]²⁺ units and ida^2? bridging ligands, while 4 offers the only example of three kinds of oa^2- ligands coexisting within the same anionic chain [(VO)₂(oa)₄^4-]_n. Their spectroscopic properties were investigated, and the magnetic susceptibility of 4 shows antiferromagnetic behavior.     

Two cadmium(II) addition compounds with 3-hydroxy-2,7-naphthalenedisulfonate containing aromatic diamines and their 3-D net

{[CdCl(2,2′-bipy)₂(H₂O)]⁺·[Cd(3-O^?-2,7-NDS)(2,2′-bipy)₂]^?·3H₂O} (1) and {[Cd(phen)₃]²⁺·2[Cd(3-O^?-2,7-NDS)(phen)₂]^?·8.5H₂O} (2) (3-OH-2,7-NDS?=?3-hydroxy-2,7-naphthalenedisulfonate, phen?=?1,10-phenanthroline, and 2,2′-bipy?=?2,2′-bipydine) were prepared and characterized by X-ray single-crystal diffraction. Compound 1 contains a discrete coordination cation [CdCl(2,2′-bipy)₂(H₂O)]⁺ and a coordination anion [Cd(3-O^?-2,7-NDS)(2,2′-bipy)₂]^?; 2 contains a discrete coordination cation [Cd(phen)₃]²⁺ and two coordination anions [Cd(3-O^?-2,7-NDS)(phen)₂]^?. There are numerous weak interactions among the coordination cation, coordination anion, and free water molecules, such as O–H?···?O hydrogen bonds, π?···?π stacking, and Cl^??···?π interactions in 1 and π?···?π stacking and C–H?···?π interactions in 2. The cations and anions as building blocks are connected to construct different 3-D supramolecular architectures via weak intermolecular interactions. Particularly, the capsule structure of 1 was observed.     

Synthesis,structure, and character of two rare earth carboxylic acid complexes

Two rare earth carboxylic acid complexes, [Sm(MeBA)₃(2,2′-bipy)]₂·2(2,2′-bipy) (MeBA = 3-methylbenzoic acid; 2,2′-bipy = 2,2′-bipyridine) (1) and [Pr(MeBA)₃(H₂O)₂]_n?n(4,4′-bipy) (4,4′-bipy = 4,4′-bipyridine) (2), have been synthesized under hydrothermal conditions and structurally determined by single-crystal X-ray diffraction. Compound 1 is a dimer and further assembles into an infinite chain, two-dimensional net and three-dimensional supramolecular structure via weak π–π and C–H···π interactions. Some 2,2′-bipy coordinates with Sm and some exist by non-covalent C–H···π interactions. Compound 2 is a 1D infinite chain structure, with adjacent 1D chains connected into a 2D layer structure by O–H···N hydrogen bonds. The two complexes were characterized by elemental analyses, IR, photoluminescence, and TGA. In order to illustrate subtle structural characteristics of intermolecular interactions and magnetic sensitivity of the complex, 2D-IR correlation spectra (2D-IR COS) under magnetic perturbation for 1 were performed.     

Five new cobalt(II) complexes based on indazole derivatives: synthesis,DNA binding and molecular docking study

Five cobalt(II) complexes based on 1H-indazole-3-carboxylic acid (H₂L), [Co(phen)(HL)₂]·2H₂O (1), [Co(5,5′-dimethyl-2,2′-bipy)(HL)₂] (2), [Co(2,2′-bipy)₂(HL)₂]·5H₂O (3), [Co₂(2,9-dimethyl-1,10-phen)₂(L)₂] (4) and [Co₂(6,6′-dimethyl-2,2′-bipy)₂(L)₂]·H₂O (5) (2,2'-bipy = 2,2′-bipyridine, phen = 1,10-phenanthroline), have been synthesized and structurally characterized by elemental analyses, IR and UV-vis spectroscopies and single-crystal X-ray crystallography. The results indicate that 1–3 possess mononuclear Co(II) structures, while 4 and 5 exhibit binuclear structure. 1D water tape which is linked by the multiple hydrogen bonds was embedded in the 3D motif of complex 3. Complexes 4 and 5 show two orthogonal planes of motif that was constituted by phen/2,2′-bipy and indazole acid, respectively. The intermolecular interactions including hydrogen bonding and π-π stacking interactions are stabilizing these complexes. The interactions of the synthesized complexes with calf-thymus DNA (CT-DNA) have been investigated by UV-vis absorption titration, ethidium bromide displacement assay and viscosity measurements. The results reveal that the complexes could interact with CT-DNA via a groove binding mode. Their behavior rationalization was further theoretically studied by molecular docking.     

Pyridine effected tunable luminescence properties of a 1D cadmium(II) polymer with tetranuclear second building units

One novel 1D polymer, [Cd₂(m-BrPhHIDC)₂(4,4′-bipy)(H₂O)₂]_n (1) (m-BrPhH₃IDC = 2-(3-bromophenyl)-1H-imidazole-4,5-dicarboxylic acid; 4,4′-bipy = 4,4′-bipyridine), has been hydrothermally synthesised and characterised by single-crystal X-ray diffraction, elemental analysis, IR, powder X-ray diffraction (PXRD) and thermogravimetric analysis. Polymer 1 composed of tetranuclear square [Cd₂(m-BrPhHIDC)₂] second building units and 4,4′-bipy bridges shows the interesting tunable luminescence properties aroused by pyridine. A luminescence enhance mechanism has been proposed.     

Synthesis and characterization of Pb(II) compounds constructed from N-tosyl-L-glutamic acid

{[Pb(tsgluo)]?·?H₂O} _n (1), [Pb₂(tsgluo)₂(phen)₂] (2), and [Pb₂(tsgluo)₂(bipy)₂] (3) (H₂tsgluo?=?N-p-tolylsulfonyl-L-glutamate, phen?=?1,10-phenanthroline, bipy?=?2,2′-pyridine) have been synthesized in the absence or presence of phen or 2,2′-bipy and structurally characterized by elemental analysis, IR, and X-ray crystallography. Single-crystal X-ray analyses reveal that tsgluo exhibits two coordination modes to link lead ions. Complex 1 gives a 2-D layer structure while 2 and 3 exhibit monomolecular structures; 3 is further connected into a double-chain structure by hydrogen bonds. Phen and 2,2′-bipy are very important for the crystal structure. Fluorescence of the compounds is also discussed.     

Architectural diversity of six coordination compounds based on (S)-(+)-mandelic acid and different N-donor auxiliary ligands: syntheses,structures, and luminescent properties

Six transition metal coordination compounds with H₂mand and different N-donor ligands, [Co(Hmand)₂(2,2′-bipy)]·H₂O (1), [Ni(Hmand)₂(2,2′-bipy)]·H₂O (2), [Ni(Hmand)₂(bpe)] (3), [Zn(Hmand)₂(2,4′-bipy)(H₂O)]·2H₂O (4), [Zn(Hmand)(bpe)(H₂O)]_n[(ClO₄)]_n·nH₂O (5), and [Zn(Hmand)(4,4′-bipy)(H₂O)]_n[(ClO₄)]_n (6), were synthesized under different conditions (H₂mand = (S)-(+)-mandelic acid, bpe = 1,2-di(4-pyridyl)ethane, 4,4′-bipy = 4,4′-bipyridine, 2,4′-bipy = 2,4′-bipyridine, 2,2′-bipy = 2,2′-bipyridine). Their structures were determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, infrared spectra, thermogravimetric analysis, powder X-ray diffraction, and circular dichroism. Compounds 1 and 2 are isostructural (0-D structures), which are extended to supramolecular 1-D chains by hydrogen bonding. Compound 3 exhibits 1-D straight chain structures, which are further linked via hydrogen bond interactions to generate a 3-D supramolecular architecture. Compound 4 displays a discrete molecular unit. Neighboring units are further linked by hydrogen bonds and π–π interactions to form a 3-D supramolecular architecture. Compound 5 displays a 2-D undulated network, further extended into a 3-D supramolecular architecture through hydrogen bond interactions. Compound 6 possesses a 2-D sheet structure. Auxiliary ligands and counteranions play an important role in the formation of final frameworks, and the hydrogen-bonding interactions and π–π stacking interactions contributed to the formation of the diverse supramolecular architectures. Compounds 1, 2, 4, 5, and 6 crystallize in chiral space groups, with the circular dichroism spectra exhibiting positive cotton effects. Furthermore, the luminescent properties of 4–6 have been examined in the solid state at room temperature, and the different crystal structures influence emission spectra significantly.     

Two new coordination host frameworks for the inclusion of 4-amino-benzophenone guest molecules

The synthesis and structural characterization of novel organometallic coordination polymers are reported. The reaction of Cd(NO₃)₂ and 4,4′-bipy in CH₃OH/H₂O gave a 2D coordination network formulated as {[Cd(4,4′-bpy)₂·(H₂O)₂](NO₃)₂·4H₂O}¹⁰, which was used to capture an organic guest species (4-amino-benezopheone, C₁₃H₁₁NO (3)) to obtain {[Cd(4,4′-bpy)₂(NO₃)(H₂O)]·NO₃·(C₁₃H₁₁NO)₂} (1). Using L (L=4,4′-trimethylenedipyridine) instead of 4,4′-bipy, {[Cd(L)₂(H₂O)₂]·2H₂O·2NO₃·C₁₃H₁₁NO} (2) was synthesized, which has an interesting configuration.     

Synthesis and crystal structure of two praseodymium 2-iodobenzoic acid complexes

Two new complexes, {[Pr(2-IBA)₃?·?2,2′-bipy]₂·[Pr(2-IBA)₃?·?2,2′-bipy]₂?·?0.5C₂H₅OH?·?H₂O} (1) and [Pr(2-IBA)₃?·?phen]₂ (2) (2-IBA?=?2-iodobenzoate; 2,2′-bipy?=?2,2′-bipyridine; phen?=?1,10-phenanthroline) were synthesized, and their crystal structures were determined by X-ray diffraction. Complex 1 consists of two binuclear molecules [Pr(2-IBA)₃?·?2,2′-bipy]₂ (a) and [Pr(2-IBA)₃?·?2,2′-bipy]₂ (b), half uncoordinated ethanol and one uncoordinated water. In the two molecules (a) and (b), the coordination environment of central ions is similar. The Pr1³⁺ ion in molecule (a) and Pr2³⁺ ion in molecule (b) are nine-coordinate with seven oxygen atoms from five 2-IBA ligands and two nitrogen atoms from one 2,2′-bipy molecule. The crystal structure of complex 2 is similar to that of binuclear [Pr(2-IBA)₃?·?2,2′-bipy]₂ in complex 1.     

Syntheses,structures, thermal stabilities and bacteriostatic activities of four lanthanide complexes

Four lanthanide complexes, [La₂(2,4-DClBA)₆(5,5′-DM-2,2′-bipy)₂(H₂O)₂]·2C₂H₅OH (1) and [Ln(2,4-DClBA)₃(5,5′-DM-2,2′-bipy)(C₂H₅OH)]₂ (Ln = Pr(2), Sm(3), Gd(4); 2,4-DClBA = 2,4-dichlorobenzoate; 5,5′-DM-2,2′-bipy = 5,5′-dimethyl-2,2′-bipyridine), were synthesized and characterized via elemental analysis, infrared spectra and thermogravimetric analysis (TG). The crystal structures of 1 and 2–4 are different; Each La³⁺ is nine-coordinate adopting a distorted mono-capped square antiprism, while the Ln³⁺ ions of 2–4 are all eight-coordinate with a distorted square antiprismatic molecular geometry. There are subtle changes in the local coordination geometry of the lanthanide–5,5′-DM-2,2′-bipy complexes. Binuclear 1 complexes are stitched together via two kinds of hydrogen bonding interactions (OH?O and CH?O) to form 1-D chains along the y axis, while the units of 2–4 are stitched together via CH?O to form 1-D chains along the x axis. TG analysis revealed thermal decomposition processes and thermal stabilities of the complexes. The bacteriostatic activities of the complexes were evaluated against Candida albicans, Escherichia coli, and Staphylococcus aureus.     

Synthesis and crystal structures of 3D supramolecular compounds: [ M (4,4′-bipy)2(H2O)4] · (4,4′-bipy)2 · (3,5-daba)2 · 8H2O ( M =Zn,Mn)

Two new supramolecular compounds [M(4,4′-bipy)₂ (H₂O)₄] ·?(4,4′-bipy)₂ ·?(3,5-daba)₂ ·?8H₂O (M=Zn(1) or Mn(2), 4,4′-bipy =?4,4′-bipyridine, 3,5-daba =?3,5-diaminobenzoic acid anion) were synthesized and characterized by elemental analysis and X-ray crystal diffraction. In [M(4,4′-bipy)₂(H₂O)₄]²⁺, the M(II) is coordinated by two nitrogen atoms from two 4,4′-bipy molecules and four oxygen atoms from four waters to form an octahedral configuration. There exist uncoordinated 4,4′-bipy molecules, 3,5-diaminobenzolate counterions and water guests in the compounds. The 3D structures of the title supramolecular compounds are constructed by rich hydrogen bonds among [M(4,4′-bipy)₂(H₂O)₄]²⁺, uncoordinated 4,4′-bipy molecules, water molecules and 3,5-daba, containing a diverting hexa-member water ring.     

Hydrothermal syntheses and structural characterization of two organic–inorganic hybrid compounds based on Lindqvist polyanions

Two organic–inorganic hybrid polyoxometalates {[V₂W₄O₁₉{Cu(2,2′-bipy)₂}₂] · (4,4′-bipy)} _n (1) and [Co(2,2′-bipy)₃][W₆O₁₉] · H₂O (2) (2,2′-bipy = 2,2′-bipyridine, 4,4′-bipy = 4,4′-bipyridine), constructed by Lindqvist polyanions and transition metal coordination cations, have been synthesized under hydrothermal conditions and characterized by elemental analysis, IR, UV spectra, thermogravimetric (TG) analyses, X-ray photoelectron spectroscopy (XPS), and single- crystal X-ray diffraction. Compound 1 is a neutral molecule and consists of a di-V^V substituted Lindqvist-type polyanion [V₂W₄O₁₉]^4?, two supporting copper cations [Cu(2,2′-bipy)₂]²⁺ and one free 4,4′-bipy. Neutral molecules of 1 are extended to a 2-D grid-like network by π–π stacking interactions between pyridine groups. The molecular structure of 2 contains one [W₆O₁₉]^2? cluster polyanion and a [Co(2,2′-bipy)₃]²⁺. Inductively coupled plasma (ICP) analysis and XPS spectrum of 1 prove the presence of V^V. TG curves of 1 and 2 indicate two weight loss steps.     

Five metal imidazole dicarboxylate-based compounds comprising M3(MIDC)2 entities (M = Zn2+, Co2+, Mn2+): syntheses,structures and properties

Five metal imidazole dicarboxylate-based compounds, {[Zn₃(MIDC)₂(4,4′-bipy)₃](4,4′-bipy)·8H₂O}_n (1), {[Co₃(MIDC)₂(4,4′-bipy)₃](4,4′-bipy)·6H₂O}_n (2), {[Co₃(MIDC)₂(py)₂(H₂O)₂]}_n (3), {[Mn₆(MIDC)₄(py)₅(H₂O)₄]}_n (4), and {[Mn₃(MIDC)₂(Phen)₃(H₂O)₂]}_n (5) (H₃MIDC = 2-methyl-1H-imidazole-4,5-dicarboxylic acid; 4,4′-bipy = 4,4′-bipyridine; py = pyridine; Phen = 1,10-phenanthroline), have been synthesized under hydrothermal conditions and characterized by elemental analyses, IR spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction. We control the coordination modes of H₃MIDC via hydrazine and obtained a series of coordination compounds containing honeycomb-like [M₃(MIDC)₂]_n layers. We also investigated the effects of different neutral terminal or bridging ligands on [M₃(MIDC)₂]_n layers. Coplanar [M₃(MIDC)₂]_n layers and 4,4-bipy were used to construct 3-D frameworks of 1 and 2. Puckered [M₃(MIDC)₂]_n layers were found in 3–5; 4 is the first [M₃(L)₂]_n layer structure with two crests and troughs during each period (L = imidazole-4,5-dicarboxylic acid or its analog). Compound 5 is the first puckered [M₃(L)₂]_n layer structure decorated by chelating neutral ligands. Compound 1 exhibits weak blue photoluminescence in the solid state at room temperature. Variable-temperature magnetic susceptibility measurements of 2–5 indicate strong antiferromagnetic interactions.     

Syntheses,structures, and properties of supramolecular complexes with bipyridine and amino-Schiff-base derived from salicylaldehyde with glycine

The reactions of stoichiometric amounts of Cu(CH₃COO)₂ · 2H₂O or Ni(CH₃COO)₂ · 2H₂O with KHL (potassium salt of salicylideneglycine) and 4,4′-bipy or 2,2′-bipy ethanol afforded [Cu₂(L)₂(μ-4,4′-bipy)(4,4′-bipy)₂] · 2H₂O (1) (L = salicylideneglycine) and Ni(OAc)₂(2,2′-bipy) (H₂O)₂ (2), respectively. The structure of 1 contains two Cu(II)'s, bridged by 4,4′-bipy; each copper is square pyramidal. Complex 2 contains a Ni(II) in highly distorted octahedral geometry. The two complexes were constructed into 3-D interwoven networks by typical H-bonding (i.e., O?H ··· O and N?H ··· O) and some other intra- or intermolecular weak interactions (i.e., C?H ··· O).     

A new ZnII two-dimensional coordination polymer, {[Zn(μ-4,4′-bipy)(1,4-ndc)(H2O)2] · (H2O)} n (4,4′-bipy= 4,4′-bipyridine and 1,4-ndc=1,4-naphthalenedicarboxylate)

A 2D Zn^II(μ-4,4′-bipy) coordination polymer with 1,4-naphthalenedicarboxylate, {[Zn(μ-4,4′-bipy)(1,4-ndc)(H₂O)₂] · (H₂O)} _n , has been synthesized, characterized and studied by X-ray crystallography. The structural studies show the Zn atoms have six-coordinate geometry with a distorted octahedral environment. The 2D structure is grown by hydrogen bonds into a hybrid three-dimensional network.