Assembly and structures of five new Cu(II) complexes based on the V-shaped building block [Cu(dbsf)]

Five new copper(II) complexes [Cu(dbsf)(H₂O)]_n · 0.5n(i-C₃H₇OH) (1), [Cu(dbsf)(4,4′-bpy)_0.5]_n · nH₂O (2), [Cu(dbsf)(2,2′-bpy)(H₂O)]₂ · (n-C₃H₇OH) · 0.5H₂O (3), [Cu(dbsf)(phen)(H₂O)]₂ · 1.5H₂O (4) and [Cu(dbsf)(2,2′-bpy)(H₂O)]_n · n(i-C₃H₇OH) (5) (H₂dbsf = 4,4′-dicarboxybiphenyl sulfone, 4,4′-bpy = 4,4′-bipyridine, 2,2′-bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline, i-C₃H₇OH = isopropanol, n-C₃H₇OH = n-propanol) have been synthesized under hydro/solvothermal conditions. All of the complexes are assembled from V-shaped building blocks, [Cu(dbsf)]. Complex 1 is composed of 1D double-chains. In complex 2, dbsf²⁻ ligands and 4,4′-bpy ligands connect Cu(II) ions into catenane-like 2D layers. These catenane-like 2D layers stack in an ABAB fashion to form a 3D supramolecular network. Complexes 3 and 4 are 0D dimers, in which two [Cu(dbsf)] units encircle to form dimetal macrocyclic molecules. However, in complex 5, the V-shaped building blocks [Cu(dbsf)] are joined head-to-tail, resulting in the formation of infinite tooth-like chains. The different structures of complexes 3 and 5 may be attributed to the different solvent molecules included.     

Hydrothermal syntheses,structures, and properties of four metal–organic coordination polymers assembled from V-shaped tetracarboxylate ligands and N-donor ancillary ligands

A series of four metal–organic frameworks, namely, [Cu(sdpa)_0.5(2,2′-bpy)]·H₂O (1), [Zn₂(sdpa)(2,2′-bpy)₂(H₂O)₂]·3H₂O (2), [Zn₂(sdpa)(4,4′-bpy)]·3H₂O (3), [Cd₂(sdpa)(4,4′-bpy)_1.5(H₂O)₂](4), have been hydro(solvo)thermally synthesized through the reaction of 2,3,2′,3′-sulfonyldiphthalic acid (H₄sdpa) with divalent copper, zinc and cadmium salts in the presence of ancillary nitrogen ligands (4,4′-bpy = 4,4′-bipyridine, 2,2′-bpy = 2,2′-bipyridine) and structurally characterized by elemental analysis, IR and X-ray diffraction. Both complex 1 and 2 show metal–organic chain structure, and the adjacent chains are further linked by π?π and C–H?π interactions for 1 and hydrogen bonds and π?π interactions for 2 to form 3D supramolecular structure. In complex 3, two Zn1 and two Zn2 atoms appear alternately and are bridged by sdpa⁴⁻ anion ligands to form an infinite Zn-sdpa chain. Such chains are further linked together through 4,4′-bpy ligands in four orientations to form a robust 3D metal–organic network. In compound 4, a 3D Cd-sdpa metal–organic network is accomplished through sdpa⁴⁻ anion ligands, and further stabilized by 4,4′-bpy in six orientations. Their luminescence and thermal analysis have also been investigated.     

Diversity of coordination modes in the polymers based on 3,3′,4,4′-biphenylcarboxylate ligand

Four new compounds [Ni₂(4,4′-bpy)(3,4-bptc)(H₂O)₄]_n (1), [Ni(4,4′-bpy)(3,4-H₂bptc)(H₂O)₃]_n (2), [Mn₂(2,2′-bpy)₄(3,4-H₂bptc)₂] (3) and {[Mn(1,10-phen)₂(3,4-H₂bptc)]·4H₂O}_n (4) (3,4-H₄bptc=3,3′,4,4′-biphenyltetracarboxylic acid, 4,4′-bpy=4,4′-bipyridine, 2,2′-bpy=2,2′-bipyridine, 1, 10-phen=1, 10-phenanthroline), have been prepared and structurally characterized. In all compounds, the derivative ligands of 3,4-H₄bptc (3,4-bptc⁴⁻ and 3,4-H₂bptc²⁻) exhibit different coordination modes and lead to the formation of various architectures. Compounds 1 and 2 display the three-dimensional (3D) framework: 1 shows a 3,4-connected topological network with (8³)(8⁵·10) topology symbol based on the coordination bonds while in 2, the hydrogen-bonding interactions are observed to connect the 1D linear chain generating a final 3D framework. 3 exhibits the 2D layer constructed from the hydrogen-bonding interactions between the dinuclear manganese units. Complex 4 shows the double layers motif through connecting the 1D zigzag chains with hydrogen-bonded rings. The thermal stability of 1-4 and magnetic property of 1 were also reported.     

A series of Cd(II) complexes with π-π stacking and hydrogen bonding interactions: Structural diversities by varying the ligands

Seven new Cd(II) complexes consisting of different phenanthroline derivatives and organic acid ligands, formulated as [Cd(PIP)₂(dnba)₂] (1), [Cd(PIP)(ox)]·H₂O (2), [Cd(PIP)(1,4-bdc)(H₂O)]·4H₂O (3), [Cd(3-PIP)₂(H₂O)₂]·4H₂O (4), [Cd₂(3-PIP)₄(4,4′-bpdc)(H₂O)₂]·5H₂O (5), [Cd(3-PIP)(nip)(H₂O)]·H₂O (6), [Cd₂(TIP)₄(4,4′-bpdc)(H₂O)₂]·3H₂O (7) (PIP=2-phenylimidazo[4,5-f]1,10-phenanthroline, 3-PIP=2-(3-pyridyl)imidazo[4,5-f]1,10-phenanthroline, TIP=2-(2-thienyl)imidazo[4,5-f]1,10-phenanthroline, Hdnba=3,5-dinitrobenzoic acid, H₂ox=oxalic acid, 1,4-H₂bdc=benzene-1,4-dicarboxylic acid, 4,4′-H₂bpdc=biphenyl-4,4′-dicarboxylic acid, H₂nip=5-nitroisophthalic acid) have been synthesized under hydrothermal conditions. Complexes 1 and 4 possess mononuclear structures; complexes 5 and 7 are isostructural and have dinuclear structures; complexes 2 and 3 feature 1D chain structures; complex 6 contains 1D double chain, which are further extended to a 3D supramolecular structure by π-π stacking and hydrogen bonding interactions. The N-donor ligands with extended π-system and organic acid ligands play a crucial role in the formation of the final supramolecular frameworks. Moreover, thermal properties and fluorescence of 1-7 are also investigated.     

A series of 2D lanthanide (III) coordination polymers constructed from 2-(pyridin-3-yl)-1H-imidazole-4,5-dicarboxylate

Reactions of 2-(pyridine-3-yl)-1H-4,5-imidazoledicarboxylic acid (H₃PyIDC) with a series of Ln(III) ions affords ten coordination polymers, namely, {[Ln(H₂PyIDC)(HPyIDC)(H₂O)₂]·H₂O}_n [Ln=Nd (1), Sm (2), Eu (3) and Gd (4)], {[Ln(HPyIDC)(H₂O)₃]·(H₂PyIDC)·H₂O}_n [Ln=Gd (5), Tb (6), Dy (7), Ho (8) and Er (9)], and {[Y₂(HPyIDC)₂(H₂O)₅]·(bpy)·(NO₃)₂·3H₂O}_n (10) (bpy=4,4′-bipyridine). They exhibit three types of networks: complexes 1-4 are isomorphous coordination networks containing neutral 2D metal-organic layers, while complexes 5-9 are isomorphous, which consist of cationic metal-organic layers and anionic organic layers, and complex 10 is a 2D network built up from 4-connected HPyIDC²⁻ anion and 4-connected Y(III) ions. In addition, thermogravimetric analyses and solid-state luminescent properties of the selected complexes are investigated. They exhibit intense, characteristic emissions in the visible region at room temperature.     

Self-assembly of four new extended architectures based on reduced polyoxometalate clusters and cadmium complexes

Four new [P₄Mo₆] cluster-based extended structures containing cadmium complexes, [Cd₃(4,4′-Hbpy)₂(4,4′-bpy)₂(H₂O)₈][Cd(H₂PO₄)₂(HPO₄)₄(PO₄)₂(MoO₂)₁₂(OH)₆]·7H₂O 1, (4,4′-Hbpy)₂[Cd(4,4′-bpy)₃(H₂O)₃][Cd(4,4′-bpy)(H₂O)]₂[Cd(H₂PO₄)₂(HPO₄)₄ (PO₄)₂(MoO₂)₁₂(OH)₆]·H₂O 2, [Cd₄(phen)₂(H₂O)₄][Cd(phen)(H₂O)]₂[Cd(HPO₄)₄ (HPO₄)₄(MoO₂)₁₂(OH)₆]·5H₂O 3 and [Cd₄(2,2′-bpy)₂(H₂O)₄][Cd(2,2′-bpy)(H₂O)]₂ [Cd(HPO₄)₄(HPO₄)₄(MoO₂)₁₂(OH)₆]·3H₂O 4 (4,4′-bpy=4,4′-bpyridine, phen=1,10-phenanthroline, 2,2′-bpy=2,2′-bpyridine), have been synthesized and characterized by elemental analysis, IR, TG and single crystal X-ray diffraction. The structure of compound 1 is constructed from the Cd[P₄Mo₆]₂ dimers linked by [Cd₃(4,4′-Hbpy)₂(4,4′-bpy)₂(H₂O)₈] subunits to generate a plane layer. Compound 2 consists of the positive 2D sheets that constructed from Cd[P₄Mo₆]₂ dimers linked by [Cd(4,4′-bpy)(H₂O)] complexes, then the 2D sheets are further linked up together to form a 3D supramolecular framework via extensive hydrogen-bonding interactions among the [P₄Mo₆] clusters, free 4,4′-bpy molecules, dissociated [Cd(4,4′-bpy)₃(H₂O)₃]²⁺ complexes and water molecules. Compounds 3 and 4 show new 2D layered structure, with Cd[P₄Mo₆]₂ building blocks connected by tetra-nuclear [Cd₄{(phen)₂/(2,2′-bpy)₂}(H₂O)₄] clusters and [Cd(phen/2,2′-bpy)(H₂O)] complexes. The fluorescent activities of compounds 3 and 4 are reported.     

Synthesis,characterization and X-ray crystallographic investigation of 2-D hybrid hydrogen bonded and rectangular grid networks in Cu(II) and Co(II) metal complexes

Two copper/cobalt metal complexes, [Cu(l-cys)(2,2′-bpy)(H₂O)] (1) and {[Co(l-cys)(4,4′-bpy)(H₂O)]·H₂O}_n (2), with the N-donor ligands 2,2′-bipyridyl/4,4′-bipyridyl and the l-cysteate dianion (l-cys) have been synthesized by different reaction methods and structurally characterized. Compound 1 exists as a discrete monomeric unit in which the metal ions possess a distorted square-pyramidal coordination environment provided by nitrogen atoms from the 2,2′-bpy ligand and the amino-carboxylate group of l-cys in a chelated coordination, constituting the square base, and with a water molecule occupying the axial coordination site to complete the penta coordination. Packing and hydrogen bonding interactions of 1 reveal that the screw related monomeric units are involved in intermolecular hydrogen bonding with the formation of helical bilayers via O–H?O and N–H?O interactions. These hydrogen bonded bilayered helical nets are involved in stacking and C–H?O interactions which generate a two dimensional hydrogen bonded network in the bc-plane. Complex 2 is a two dimensional coordination polymer which is insoluble in common polar and non-polar solvents. The coordination around the metal center possesses a distorted octahedral geometry. The adjacent metal centers are bridged via the carboxylate group of the l-cys moiety in a syn–anti fashion, generating a one dimensional helical network along the b-axis. Adjacent helical chains are further pillared by the 4,4′-bpy ligand through the terminal nitrogen atoms, generating a two dimensional square grid type coordination network. Both the complexes are characterized well by various physico-chemical techniques such as CHN analysis, IR spectroscopy, PXRD and CD analysis.     

Architecture of zero-, one-, two- and three-dimensional structures based on metal ions and pyrazine-2,6-dicarboxylic acid

Six new complexes: [Ln₂(pzda)₃(H₂O)₂] · 2.5H₂O (Ln = Nd, (1); Eu, (2)), [Co(pzda) (bpe)] · 0.125(bpe) · 1.75H₂O (3), [Mn(pzda)(H₂O)_1.5] (4), [Co₂(pzda)₂(bpe)(H₂O)₄] · 0.5(CH₃OH) · H₂O (5) and [Co(pzda)(2,2′-bpy)(H₂O)] · 0.5H₂O (6) (H₂pzda = pyrazine-2,6-dicarboxylic acid, bpe = 1,2-bis(4-pyridyl)ethane, 2,2′-bpy = 2,2′-bipyridine) were obtained from metal salts and H₂pzda under hydro(solvo)thermal conditions. The single crystal X-ray structural analysis reveals that the title complexes have different structures, ranging from zero- to three- dimensions, which are mainly due to the different metal ions, and especially the coordination modes of the pzda ligands. Complexes 1 and 2 have 3D metal-organic frameworks containing a 1D tri-strand array, in which the pzda ligand adopts a pentadentate mode to link lanthanide ions. Complex 3 has a 2D metal-organic framework, in which the pzda ligand acts in a tetradentate mode to connect Co(II) ions into 1D chains, which are further connected by bpe spacers into a 2D framework. While in 4, both of the two carboxylate groups of the pzda ligand adopt μ₂-O bridging modes to link Mn(II) ions into a 1D coordination polymer, which is further assembled into a 2D supramolecular network containing double-stranded hydrogen-bonded helical chains. In both 5 and 6, the pzda ligand binds metal ions as a tridentate ligand (ONO mode) to form zero dimensional structures. Complex 5 is a binuclear molecule, while 6 is a mononuclear complex, which can be attributed to the bridging ligand bpe for 5 and the terminal auxiliary ligand 2,2′-bpy for 6.     

Synthesis and characterization of coordination polymers of a carboxylato cyclophane with metal [Zn(II) and Cd(II)]-2,2′-bipyridines

N,N′,N′′,N′′′-Tetrakis(3-carboxy-propionyl)-1,6,20,25-tetraaza-[6.1.6.1] paracyclophane, H₄cp has been complexed with metal (Zn(II) and Cd(II)) 2,2′-bipyridyls. The resulting complexes of the composition [{Zn(2,2′-bpy)}₂(cp)]_n·4H₂O 1 and [{Cd(2,2′-bpy)}₂(cp)]_n·5H₂O 2 (2,2′-bpy = 2,2′-bipyridine) have been characterized using spectroscopic (IR, solid state UV–Vis), elemental analysis and single-crystal X-ray diffraction measurements. In these complexes the cyclophane coordinates in different modes, and in complex 2, Cd(II) is hepta-coordinated. However, under harsh reaction conditions (using excess nitric acid and a longer reaction time) debranching of the cyclophane is observed in the reaction of Zn(2,2′-bpy)(NO₃)₂ with H₄cp, and a complex of the composition [Zn(2,2′-bpy)(Suc)]_n3 (suc = succinate) is isolated. Using non-covalent interactions, complexes 1 and 2 provide 3D supramolecular structures, whereas an infinite 1D chain structure is observed for complex 3. The thermal and photoluminescence properties of the complexes have also been studied.     

Organic-inorganic hybrids constructed by Anderson-type polyoxoanions and copper coordination complexes

Four organic-inorganic hybrid compounds based on Anderson-type polyoxoanions, namely, {[Cu(2,2′-bpy)(H₂O)₃]₂[Cr(OH)₆Mo₆O₁₈]}{[Cu(2,2′-bpy)(H₂O)Cl][Cu(2,2′-bpy)(H₂O)(NO₃)][Cr(OH)₆Mo₆O₁₈]}·18H₂O (1), [Cu(2,2′-bpy)(H₂O)₂Cl]{[Cu(2,2′-bpy)(H₂O)₂][Cr(OH)₆Mo₆O₁₈]}·4H₂O (2), (H₃O){[Cu(2,2′-bpy)(H₂O)₂]₂[Cu(2,2′-bpy)(H₂O)]₂}[Cr(OH)₆Mo₆O₁₈]₃·36H₂O (3), and (H₃O){[Cu(2,2′-bpy)(H₂O)₂]₂[Cu(2,2′-bpy)(H₂O)]₂}[Al(OH)₆Mo₆O₁₈]₃·33H₂O (4), were isolated by conventional solution method, and crystal structures have been determined by single-crystal X-ray diffraction. Among them, compound 1 displays a discrete supramolecular structure, compound 2 shows a chainlike structure with chloro-copper complexes as counteranions, and compounds 3 and 4 are isomorphic and exhibit unique 3D open frameworks with lattice water molecules residing in the channels. The compounds 3 and 4 represent the first example of 3D organic-inorganic hybrid compounds in the TMs/2,2′-bpy/POMs system. Investigation of the reaction conditions reveals that the geometry and size of the anions together with its coordinating abilities to the metal centers have a decisive influence on both the composition and the dimensionality of the final compounds.     

A series of metal-organic frameworks constructed with arenesulfonates and 4,4′-bipy ligands

Five transition metal compounds containing arenesulfonates and 4,4′-bipy ligands, namely [Zn₂(N,N′-4,4′-bipy)(N-4,4′-bipy)₂(H₂O)₈](bpds)₂ · 5H₂O (1), [Ag₂(N,N′-4,4′-bipy)₂(bpds)] (2), [Cd(N,N′-4,4′-bipy)(H₂O)₄]₂(4-abs)₄ · 5H₂O (3), [Cu(N,N′-4,4′-bipy) (O-bs)₂(H₂O)₂] · 4H₂O (4), and [Zn(N,N′-4,4′-bipy)₂(H₂O)₂](4,4′-bipy)(bs)₂ · 4H₂O (5) (4,4′-bipy = 4,4′-bipyridine, bpds = 4,4′-biphenyldisulfonate, 4-abs = 4-aminobenzenesulfonate, bs = benzenesulfonate), have been synthesized and characterized by X-ray single crystal diffraction, elemental analyses and TG analyses, in order to investigate the coordination chemistry of arenesulfonates and 4,4-bipy, as well as to construct novel coordination frameworks via mixed-ligand strategy. Compounds 2, 4 and 5 could be obtained via hydrothermal or aqueous reactions. Compound 1 forms a binuclear octahedral metal complex. Compounds 2–4 form polymeric chains. Compound 5 consists of 2D square grids with one intercalated 4,4′-bipy molecule. Weak Ag–Ag interactions are observed in compound 2. These complexes show great structural varieties and there are three different coordination modes observed for both the 4,4′-bipy and the sulfonate ligands.     

Coordination polymers with the chiral ligand N-p-tolylsulfonyl-l-glutamic acid: Influence of metal ions and different bipyridine ligands on structural chirality

Four new polymers, namely [Ni(-tsgluO)(2,4′-bipy)₂(H₂O)₂]_n·5nH₂O (1), [Co(-tsgluO)(2,4′-bipy)₂(H₂O)₂]_n·5nH₂O (2), [Ni(-tsgluO)(4,4′-bipy)]_n·0.5nH₂O (3), and [Co(-tsgluO)(4,4′-bipy)]_n·0.5nH₂O (4), where tsgluO²⁻=(+)-N-p-tolylsulfonyl-l-glutamate dianion, 2,4′-bipy=2,4′-bipyridine, and 4,4′-bipy=4,4'-bipyridine, have been prepared and structurally characterized. Compounds 1 and 2 are isostructural and mononuclear, and crystallize in the acentric monoclinic space group Cc, forming 1D chain structures. Compound 3 is also mononuclear, but crystallizes in the chiral space group P2₁, forming a homochiral 2D architecture. In contrast to the other complexes, compound 4 crystallizes in the space group P−1 and is composed of binuclear [Co₂O₆N₂]_n⁴⁻ units, which give rise to a 2D bilayer framework. Moreover, compounds 1, 2, and 4 self-assemble to form 3D supramolecular structures through π-π stacking and hydrogen-bonding interactions, while compound 3 is further hydrogen-bonded to form 3D frameworks. We have demonstrated the influence of the central metal and bipyridine ligands on the framework chirality of the coordination complexes.     

Synthesis, crystal structures and photoluminescent properties of lanthanide supramolecular complexes with 4-oxo-1(4H)-quinolineacetate

Five new lanthanide supramolecular complexes, namely, [Sm(oqa)₂(H₂O)₄]₂ (ClO₄)₂·(bpy)₂ (1), [Ln(oqa)₃]·2H₂O [Ln=Sm(2), Gd(3)] and [Ln(oqa)₂(NO₃)(H₂O)] [Ln=Pr(4), Eu(5)] (oqa=4-oxo-1(4H)-quinolineacetate, bpy=4,4′-bipyridine), have been synthesized under hydrothermal conditions. These complexes exhibit three typical structure features. Complex 1 possesses a dimeric structure, which is further connected together through hydrogen bonds and π-π attractions, forming a 3D supramolecular framework. Compounds 2-3 are isomorphous and contain 1D ring-like chains, which are further interconnected by the oqa ligands into 2D sheet-like structures. 4 and 5 exhibit eight-connected 3D network of 4²⁴·6⁴-bcu topology. The various coordination modes of carboxylate ligands and the selection of the counterions have clearly affected the topological structures. Furthermore, the solid-state luminescent properties of complexes 1, 2 and 5 were investigated at room temperature and they show intense, characteristic emissions in the visible region.     

Crystal structures and properties of four coordination polymers constructed from flexible pamoic acid

Four novel coordination polymers constructed from flexible pamoic acid, namely [Co(pam)(4,4′-bipy)]_n·nH₂O (1), [Ni(pam)(4,4′-bipy)(H₂O)₂]_n·2nCH₃CN (2), [Cd(pam)(py)₂]_n·npy (3) and [Mn₂(pam)₂(py)₆(H₂O)₂]_n·2npy (4), (H₂pam = pamoic acid, 4,4′-bipy = 4,4′-bipyridine, py = pyridine), have been synthesized and characterized by elemental analysis, infrared spectra and X-ray crystallography. Complex 1 is a 2-D coordination polymer constructed from chelating bis-bidentate pam and 4,4′-bipyridine bridging ligands. Complex 2 is a 2-D coordination polymer assembled by bis-monodentate pam and 4,4′-bipyridine, where acetonitrile is filled in the rectangle channels. Both 2-D coordination polymers display undulated (4,4) grid layers as sql topology. Complex 3 displays a 1-D polymeric chain using chelating bis-bidentate pam as bridging ligand. Complex 4 exhibits an interesting bis-monodentate pam-Mn(II) 1-D polymeric chain, in which exist two-type six-coordinated manganese centers. Mn(1) is bound to four pyridine ligands, whereas Mn(2) is combined to two pyridine and two H₂O molecules. Their thermal stabilities have been investigated. Cadmium complex 3 displays strong green luminescence with emission maximum at 543 nm.     

Syntheses,structures, network topologies and photoluminescence of four Zn(II) and Cd(II) coordination polymers based on 5-carboxyl-1-carboxymethyl-2-oxidopyridinium

5-Carboxyl-1-carboxymethyl-2-oxidopyridinium (H₂CCOP) and a combination of N-donor ligands, such as 4,4′-bipyridine (4,4′-bipy) and 1,10-phenanthroline (phen) with d¹⁰ metal ions Zn(II) and Cd(II) give rise to four coordination polymers, namely, [Zn₂(CCOP)(OH)₂(H₂O)] (1), [Zn(CCOP)(phen)(H₂O)]·H₂O (2), [Cd(CCOP)(H₂O)₂]·3H₂O (3), and [Cd(CCOP)(H₂O)] (4). Polymer 1 features an unusual bilayer motif and forms the final (3,8)-connected 3D topology by hydrogen bonds. Polymer 2 consists of one-dimensional (1D) chains which are further connected with each other via hydrogen bonds to form the final interesting (3,6)-connected rutile network. Polymer 3 is made up of an unusual 2D structure containing cylinder channels in the b axis and features the (4,4)-connected 3D network by hydrogen bonds. Polymer 4 presents an interesting uninodal 4-connected net compared to polymer 3. These four coordination polymers are obtained by evaporation or hydrothermal route and characterized by analytical, spectroscopic, and crystallographic methods. Photoluminescence studies revealed that these four coordination polymers display structure-related fluorescent emission bands (λ_ex = 342 nm) at 361 nm for polymer 1, 404 nm for polymer 2, 367 nm for polymer 3, and 371 nm for polymer 4 in the solid state at room temperature.     

Hydrothermal syntheses, structures and characterizations of three one-dimensional polyoxomolybdates with 4,4′-dimethylenebiphenyl diphosphonic acid as bridge

Three heterometallic 1-D polymers, [{Ni(1,10-phen)₂(H₂O)}₂ {(Mo₅O₁₅)(4,4′-dbp)}·(5.75H₂O)] (4,4′-dbp=O₃PCH₂C₆H₄C₆H₄CH₂PO₃) (1), [{Co(1,10-phen)₂(H₂O)}₂ {(Mo₅O₁₅)(4,4′-dbp)}·(5.5H₂O)] (2) and [{Ni(2,2′-bpy)₃}{Ni(2,2′-bpy)₂(H₂O)} {(Mo₅O₁₅)(4,4′-dbp)}·(4.75H₂O)] (3), have been synthesized under hydrothermal conditions. Their structures were determined by single crystal X-ray diffraction. The 1-D chains is constructed of [Mo₅O₁₅(4,4′-dbp)]⁴⁻ units, which are further decorated and charge compensated by [M(1,10-phen)₂] (M=Ni, Co) or [Ni(2,2′-bpy)₂] subunits. The thermogravimetric analyses and magnetic properties of 1 and 2 were studied.     

From platina-β-diketones to diacetylplatinum(II) complexes - Synthesis, characterization and structural features

The reaction of the electronically unsaturated platina-β-diketone [Pt₂{(COMe)₂H}₂(μ-Cl)₂] (1a) with N^?N donors led to the formation of diacetyl(hydrido)platinum(IV) complexes [Pt(COMe)₂Cl(H)(N^?N)] (2). By the reaction of these complexes with NaOH in a two-phase system (H₂O/CH₂Cl₂) diacetylplatinum(II) complexes [Pt(COMe)₂(N^?N)] (N^?N = bpy, 4a; 4,4′-Me₂-bpy, 4b; 4,4′-t-Bu₂-bpy, 4c; 4,4′-Ph₂-bpy, 4d; 4,4′-t-Bu₂-6-n-Bu-bpy, 4e; bpym, 4f; bpyr, 4g; phen, 4h; 4-Me-phen, 4i; 5-Me-phen, 4j) were obtained. All complexes were characterized by microanalysis, IR and ¹H and ¹³C NMR spectroscopy. Additionally, complexes 4a, 4c, 4d and 4e were characterized by single-crystal X-ray diffraction analysis. The observed variety of packing patterns resulting from π-π stacking and hydrogen bonding is discussed.     

Luminescent lanthanide complexes with 4-acetamidobenzoate: Synthesis, supramolecular assembly via hydrogen bonds, crystal structures and photoluminescence

Four new luminescent complexes, namely, [Eu(aba)₂(NO₃)(C₂H₅OH)₂] (1), [Eu(aba)₃(H₂O)₂]·0.5 (4, 4′-bpy)·2H₂O (2), [Eu₂(aba)₄(2, 2′-bpy)₂(NO₃)₂]·4H₂O (3) and [Tb₂(aba)₄(phen)₂(NO₃)₂]·2C₂H₅OH (4) were obtained by treating Ln(NO₃)₃·6H₂O and 4-acetamidobenzoic acid (Haba) with different coligands (4, 4′-bpy=4, 4′-bipyridine, 2, 2′-bpy=2, 2′-bipyridine, and phen=1, 10-phenanthroline). They exhibit 1D chains (1-2) and dimeric structures (3-4), respectively. This structural variation is mainly attributed to the change of coligands and various coordination modes of aba molecules. Moreover, the coordination units are further connected via hydrogen bonds to form 2D even 3D supramolecular networks. These complexes show characteristic emissions in the visible region at room temperature. In addition, thermal behaviors of four complexes have been investigated under air atmosphere. The relationship between the structures and physical properties has been discussed.     

Hydrothermal synthesis,crystal structures,and properties of two 3-D network nickel nicotinate coordination polymers: [Ni4(μ-H2O)2(nicotinate)8 · 2H2O] and [Ni2(H2O)2(nicotinate)4(4,4′-bpy)]

The three-dimensional coordination polymers [Ni₄(μ-H₂O)₂(nic)₈ · 2H₂O] (nic = nicotinate, 3-pyridylcarboxylate) (1) and [Ni₂(H₂O)₂(nic)₄(4,4′-bpy)] (2) were prepared by the hydrothermal reaction of nickel(II) chloride, nicotinic acid, sodium hydroxide and an organoimine (several choices for 1, 4,4′-bipyridine for 2). The non-centrosymmetric crystal structure of 1 is constructed from binuclear [Ni₂(μ-H₂O)(μ₃-nic)₂]²⁺ subunits joined into 3-D via μ₂- and μ₃-nicotinate ligands, forming “bird”-shaped cavities that contain water molecule dimers. The crystal structure of 1 is compared and contrasted to two previously reported nickel(II) nicotinate phases. In contrast, the crystal structure of 2 is assembled from neutral [Ni(H₂O)(μ₂-nic)₂] layers, connected into 3-D via tethering 4,4′-bpy moieties. 1 exhibits weak antiferromagnetic coupling across its binuclear subunits (J = −1.61(2) cm⁻¹ for g = 2.233(2)), although anisotropy due to single-ion zero-field-splitting (D) cannot be excluded. The 3-D structures of 1 and 2 remain stable above 300 °C and 200 °C, respectively.     

Hydrothermal syntheses, crystal structures and properties of three coordination frameworks based on a new semirigid ligand and benzenedicarboxylate

Three novel polymers, {[Cd(m-bdc)(L)]·H₂O}_n (1), [Co(m-bdc)(L)_0.5(H₂O)]_n (2) and [Zn₅(L)₂(p-bdc)₅(H₂O)]_n (3) based on 1,1′-bis(pyridin-3-ylmethyl)-2,2′-biimidazole (L) ligand and benzenedicarboxylate isomers, have been prepared and structurally characterized. Compound 1 exhibits a 2D architecture with (4²·6)(4²·6⁷·8) topology, which is synthesized by L and 1,3-benzenedicarboxylate (m-bdc) ligands. Compound 2 is constructed from 1D chains that are linked by L ligands extending a 2D (4,4) grid. Compound 3 is a 3D framework with (4³)(4⁶·6¹⁸·8⁴) topology, which is composed of trinuclear clusters and five-coordinated metal centers joined through 1,4-benzenedicarboxylate (p-bdc) and L ligands. Moreover, the fluorescent properties of L ligand, compounds 1 and 3 are also determined.