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Reaction of copper salts and D-(–)-quinic acid (H5L) yielded three complexes, [Cu(H2O)(H3L)]2·2H2O1, [Cu(H2O)(H4L)(NO3)]n·(H2O)n2, and [Cu(H2O)(H4L)(ClO4)]n·(2H2O)n3. An interesting law was observed that solvent selection influenced the structural assemblies, namely, in an aqueous solution utilizing CuCl2·2H2O/Cu(NO3)2·6H2O/Cu(ClO4)2·6H2O and D-(–)-quinic acid only obtained [Cu(H2O)(H3L)]2·2H2O1,while the environment was replaced by an alcoholic system, afforded three polymers: [Cu(H2O)(H4L)Cl]n·(H2O)n4, [Cu(H2O)(H4L)(NO3)]n·(H2O)n2, and [Cu(H2O)(H4L)(ClO4)]n·(2H2O)n3, respectively. Complex1crystallizes in the polar monoclinicC2 space group, while complexes2and3in the nonpolar orthorhombic space groupP212121. In compound1, the binuclear Cu(II) units are assembled into 3D network through hydrogen bonds and the overall topology can be described as a 7-connected dinodal net topology of (36·48·57) with the Schläfli symbol of (3.3.3.3.3.3.4.4.4.4.4.4.4.4.5.5.5.5.52.52.52). In2and3, the D-(–)-quinic acid anions are function as tetradentate ligands bridging Cu(II) ions to build up 3D metal-organic frameworks (MOFs) with {103} topological representation. The polar complex1displays a promising ferroelectricity with a remnant polarization (Pr) ofca.0.07 μC/cm2, coercive field (Ec) ofca.2.43 kV/cm, and saturation of the spontaneous polarization (Ps) ofca.0.128 μC/cm2. The magnetic behavior of1suggests significant antiferromagnetic coupling interactions between Cu(II) ions bridged by carboxylic groups, while considerable ferromagnetic coupling interactions in complexes2and3. Furthermore, the title complexes1–3were subjected to microelement analyses, IR spectroscopic measurements, and thermal analyses. [ABSTRACT FROM PUBLISHER]

One-pot reactions of Cu(ClO4)2·6H2O, phenanthroline (phen), malonic acid (H2mal) and NaOH in molar ratio 1:1:1:2 (mmol) in 40mL H2O/MeOH afforded two novel complexes [Cu2(phen)2(H2O)3(mal)(ClO4)](ClO4) ([4]ClO4) and [Cu6(phen)6(H2O)2(mal)4(ClO4)2](ClO4)2 ([5](ClO4)2) besides three known complexes [Cu(phen)2(H2O)](ClO4)2 ([1](ClO4)2), [Cu(phen)(H2O)(mal)]·1.5H2O ([2]·1.5H2O) and [Cu3(phen)3(H2O)2(mal)3]·11H2O ([3]·11H2O). Complexes [2]·1.5H2O, [3]·11H2O, [4]ClO4 and [5](ClO4)2 commonly have a basic building motif of a general formulation [Cu(phen)(mal)X] n with the Cu square-pyramidally coordinated by phen molecule, (mal−) anion and an apical X group (X=H2O, ClO4 −, [Cu(phen)(H2O)(mal)], n =0, +1). [3]·11H2O is built up of the hydrogen-bonded [Cu3(phen)3(H2O)2(mal)3] trimers and (H2O)11 clusters, while [4]ClO4 and [5](ClO4)2 feature 1D {[Cu2(phen)2(H2O)3(mal)](ClO4)2/2}+ chain and hexanuclear [Cu6(phen)6(H2O)2(mal)4(ClO4)2]2+ complex cations, respectively. Self-assembly routes to the malonate-based Cu(II) phenanthroline complexes were well established on the basis of the [Cu(phen)(H2O)(mal)] complex molecule. Both acentric polar complexes [3]·11H2O and [4]ClO4 represent the first two examples of metal malonato complexes with ferroelectric property with a remnant polarization (Pr) of ca. 0.045 and 0.2002μCcm−2, coercive field (Ec) of ca. 0.70 and 1.79kVcm−1, and saturation of the spontaneous polarization (Ps) at ca. 0.39 and 0.248μCcm−2, respectively. The magnetic properties of [4]ClO4 and [5](ClO4)2 follow Curie–Weiss law χm = C/(T − Θ) with the Curie constant C =0.480(2), 0.587(7)cm3 mol−1 K and Weiss constant Θ =0.32(1), 0.61(2)K, respectively. The weak ferromagnetic behaviors can be well analyzed using dinuclear Cu2 and V-shaped trinuclear Cu3 models, respectively, and best-fittings gives J =6.2(6)cm1 for equatorial–equatorial syn–anti μ-COO groups. [ABSTRACT FROM AUTHOR]

The title compound [Mn(bpp)2(C4O4)]·H2O (1) was obtained by reaction of acetylenedicarboxylic acid, fresh MnCO3and 1,3-bis(4-pyridyl)propane (bpp) in aqueous ethanol solution under 80°C. The Mn ions are bridged by acetylenedicarboxylate into a 1D zigzag chain, which is interlinked by bpp ligand to generate a 3D six-connected framework with the Schläfli symbol (48·67). The temperature dependence of the magnetic susceptibility of the complex follows the Curie-Weiss law, and the magnetic behavior can be interpreted by means of 1D chain model. The best fit results in J = 0.03(1) cm−1, indicating weak ferromagnetic coupling. [ABSTRACT FROM AUTHOR]

Three new pyridine-2,3,5,6-tetracarboxylato (H4pdtc) complexes K2[Mn(H2O)(pdtc)]·3H2O 1, Na2[M3(H2O)6(pdtc)2]·6H2O (M=Mn 2, Co 3) were obtained and characterized by single-crystal X-ray diffraction methods and magnetic measurements. The characteristic building blocks of 1–3 are the pdtc bridged stair-like chains {[M(H2O)](pdtc)3/3}2–, which results from the six-coordinated transition metal atoms bridged by pdtc4− ligands. The infinite chains in 1 are assembled by hydrogen bonds into 2D supramolecular networks, which are held together by (4·82) topological K+–H2O networks to complete 3D architecture. While the stair-like chains in 2 and 3 are interconnected by trans-[M(H2O)4]2+ moieties to 2D polymeric layers, which are bridged by dimeric [Na2(μ-H2O)2(H2O)2]2+ moieties to build up 3D framework. The magnetic properties of 1–3 were analyzed on the basis of (i) linear trinuclear M3 models and (ii) the free Mn2+ and Co2+ ions with the zero-field splitting effect and spin–orbit coupling effect, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Two coordination polymers, [Y(H2O)4(H3chhc)]·6H2O (1) and [Cu5(H2O)10(Hchhc)2]·4H2O (2) with H6chhc=cyclohexane-1,2,3,4,5,6-hexacarboxylic acid) represent rare examples of metal complexes with partially protonated cyclohexane-1,2,3,4,5,6-hexacarboxylato ligands. The [Y(H2O)4]3+ units in 1 are interlinked by the triprotonated (H3chhc)3− anions in a η5μ4 bridging mode to form 2D (43)2(46·66·83) topological networks, which are stacked along [010] direction in ···ABAB··· fashion with the lattice H2O molecules sandwiched between layers. The pentameric [Cu5(H2O)10]10+ units in 2 are bridged by monoprotonated (Hchhc)5− anions in a η8μ6 fashion to generate a 3D MOF of an unprecendented (43)(45·67·83) topology with the lattice H2O molecules in channels. The temperature-dependent magnetic susceptibility data of 2 could be modeled to a combination of a linear chain of equally-spaced Cu(II) ions (J 1 =1.86cm−1) with an isosceles triangular Cu3 unit (J 2 =5.86cm−1). [Copyright &y& Elsevier]

Abstract: Four tetrahydrofuran-2,3,4,5-tetracarboxylato bridged copper(II) coordination polymers with alkali metals, Na2[Cu(H2O)(THFTC)]·5H2O 1, K2[Cu3(H2O)2(THFTC)2]·9H2O 2, Rb2[Cu3(H2O)2(THFTC)2]·6H2O 3 and Cs2[Cu3(H2O)2(THFTC)2]·6H2O 4 (H4THFTC=tetrahydrofuran-2,3,4,5-tetracarboxylic acid) were prepared from reactions of Cu(NO3)2·3H2O, tetrahydrofuran-2,3,4,5-tetracarboxylic acid and alkali hydroxide or carbonate at pH 5.0–6.0 under ambient conditions. Compound 1 features 2D (33·43·54) topological layers generated from six-coordinated Cu2+ cations interlinked by (THFTC)4− anions, and the resulting layers are ecliptically stacked along [100] direction to form lozenge-shaped and octagonal channels filled with Na+ ions and lattice H2O molecules. In 2–4, both penta- and hexa-coordinated copper(II) ions are bridged by tetracarboxylate anions to form negatively charged 2D layers formulated as 2 ∞[Cu(H2O)2L3/2]2− with the corresponding alkali metal cations (K+, Rb+ or Cs+ ions) and hydrogen bonded lattice H2O molecules sandwiched between them. Additionally, the results about i.r. spectroscopic, thermal characterizations and magnetic properties are presented. [Copyright &y& Elsevier]

A novel dinuclear nickel(II) complex Ni2(NO3)4(APTY)4 (1) (APTY = 1,5-dimethyl-2-phenyl-4-{[(1E)-pyridine-4-ylmethylene]amino}-1,2-dihydro-3H-pyrazol-3-one), was synthesized by solvothermal reaction of Ni(NO3)2 · 6H2O with APTY in methanol at 353 K. The structure consists of centrosymmetric dimers resulting from octahedrally coordinated Ni atoms bridged by APTY ligands. Weak intermolecular interactions (C-H ··· N, C-H ··· O hydrogen bonding, C-H ··· π and π-π stacking interactions) are responsible for a supramolecular assembly of molecules in the lattice. Magnetic measurements over 1.8-300 K show weak antiferromagnetic coupling between Ni(II) ions with J = 2.969 cm-1, g = 2.280, θ = -5.903. [ABSTRACT FROM AUTHOR]

Two fumarato-bridged coordination polymers M(H2O)2(C4H2O4), with M?=?Cu (1) and Cd (2), were prepared and structurally characterized using single-crystal X-ray methods. In 1, Cu atoms are coordinated by two aqua oxygen atoms at trans positions and three oxygen atoms of different fumarate anions to form a square pyramid; two adjacent CuO5 square pyramids share edges to form Cu2O8 dimers. Cd atoms in 2 are coordinated by seven oxygen atoms of two aqua ligands and three different fumarate anions to form a distorted pentagonal bipyramid, with two adjacent pentagonal bipyramids sharing a common edge to form Cd2O12 dimers. Both dimers in 1 and 2 are bridged by fumarato ligands to generate open layers with a (4,?4) topology. Close packing of the layers prevents formation of porous 3D networks. The magnetic behavior of 1 was investigated. [ABSTRACT FROM AUTHOR]

Two malonato-bridged hexamethylenetetramine coordination polymers, M 2 (hmt)(H 2 O) 2 (mal) 2 [hmt = hexamethylenetetramine, mal = malonate(2-), M = Mn ( 1 ), Cu ( 2 )] were prepared and structurally characterized. The isostructural complexes are orthorhombic, space group Imm 2, with a = 7.104(1), b = 15.982(3), c = 7.702(1) Å, Z = 2, D calc = 1.862 g cm -3 ( 1 ) and a = 6.962(3), b = 15.500(7), c = 7.627(3) Å, Z = 2, D calc = 2.047 g cm -3 for 2 . The transition metals are octahedrally coordinated by one nitrogen atom of an hmt ligand and five oxygen atoms of a water molecule and three malonate anions. The latter coordinate in chelating/ bis -monodentate mode to give 2D layers with a (4, 4) topology, and which are pillared by bridging bidentate hmt ligands to generate an open 3D framework with channels extending in the [001] direction. Over the temperature range 5-300 K, 2 behaves paramagnetically, following the Curie-Weiss law χ m ( T - θ) = 4.521(6) cm 3 mol -1 K with a Weiss constant θ = -4.8(2) K. [ABSTRACT FROM AUTHOR]

Abstract: Four 4,4′-bipyridine α,ω-dicarboxylate coordination polymers Cu(bpy)(C5H6O4) (1), Zn(bpy)(C5H6O4) (2), Zn(bpy)(C6H8O4) (3) and Mn(bpy)(C8H12O4)·H2O (4) have been synthesized and structurally characterized by single crystal X-ray diffraction methods (bpy=4,4-bipyridine, (C5H6O4)2−=glutarate anion, (C6H8O4)2−=adipate anion, (C8H12O4)2−=suberate anion). Their crystal structures are featured by dimeric metal units, which are co-bridged by 4,4′-bipyridine ligands and dicarboxylate anions such as glutarate, adipate and suberate anions to generate 2D layers with a (4,4) topology in 1, 2 and 4 as well as to form 3D frameworks in 3. Two 3D frameworks in 3 interpenetrate with each other to form a topology identical to the well-known Nb6F15 cluster compound. Over 5–300K, the paramagnetic behavior of 4 follows the Curie–Weiss law χm(T−Θ)=4.265(5)cm3mol−1 with the Weiss constant Θ=−6.3(2)K. Furthermore, the thermal behavior of 3 and 4 is also discussed. [Copyright &y& Elsevier]

[Co2(phen)2(H2O)2L2]·5H2O 1 and {Co[Co(phen)(H2O)4]2L4/2}L·4H2O 2 (H2L=suberic acid, HOOC–(CH2)6–COOH) were prepared by reaction of phenanthroline and suberic acid with freshly-precipitated CoCO3·xH2O and Co(OH)2·yH2O, respectively, in EtOH/ H2O. Compound 1 consists of the centrosymmetric dinuclear [Co2(phen)2(H2O)2L2] complex molecules and hydrogen bonded H2O molecules and the complex molecules are assembled via π–π stacking interactions and weak C–H⋯O hydrogen bonds to generate 2D layers, whose assembly based on O–H⋯O hydrogen bonds results in 3D framework with the crystal H2O molecules in tunnels. The crystal structure of 2 featured the polymeric ∞1{Co[Co(phen)(H2O)4]2L4/2}2+ cationic chains from bis-monodentate suberato ligands doubly bridging trinuclear {Co[Co(phen)(H2O)4]2}6+ units, in which the central Co atom is coordinated via μ2-H2O molecules to two [Co(phen)(H2O)4]2+ complex ligands. Through π–π stacking interactions, the polymeric cationic chains are held together into 2D layers, which are further connected by suberate anions and lattice H2O molecules. The thermal and magnetic behavior of 1 and 2 is discussed. [Copyright &y& Elsevier]

The complex [Ni(H2O)3(phen)(C4H2O4)] ⋅ H2O ( 1), which was obtained by reaction of phenanthroline, Ni(NO3)2 ⋅ 6H2O, and maleic acid in CH3OH/H2O at pH = 7.05, crystallized in the monoclinic space group P21 (no. 4) with cell dimensions: a = 9.350(1) Å, b = 7.631(1) Å, c = 12.821(1) Å, β = 106.25(1), and Dcalc = 1.607 g/cm3 for Z = 2. The Ni atoms are each octahe drally coordinated by one chelating phen ligand, three H2O molecules and one monodentate maleato ligand to form [Ni(H2O)3(phen)(C4H2O4)] complex molecules with d(Ni–O) = 2.038–2.090 Å, d(Ni–N) = 2.066, 2.089 Å. The formed complex molecules are, via the intermolecular hydrogen bonds, assembled into columnar 1D chains. Interdigitation of the chelating phen ligands of the neighboring chains leads to 2D layers and the crystal H2O molecules are hydrogen bonded to the oxygen atoms of the maleate not coordinated to the Ni atom. However, reaction of NiCO3, phen, and maleic acid in CH3OH/H2O at pH = 6.33 afforded [Ni(H2O)2(phen)(C4H2O4)] ⋅ 2H2O ( 2), which crystallized in the triclinic space group $$P\bar 1$$ (no. 2) with cell dimensions: a = 7.971(1) Å, b = 8.237(1) Å, c = 13.304(1) Å, α = 81.005(6)°, β = 87.877(8)°, γ = 78.322(8)°, and Dcalc = 1.671 g/cm3 for Z = 2. The Ni atoms are each octahedrally coordinated by two N atoms of one phen ligand and four O atoms of two H2O molecules and two bis–monodentate maleato ligands with d(Ni–O) = 2.041–2.120 Å and d(Ni–N) = 2.095 Å. The Ni atoms are bridged by the maleato ligands to generate 1D [Ni(H2O)2(phen)(C4H2O4)2/2] chains along [100]. The supramolecular assemblies of the 1D chains via π–π stacking inter- actions result in thick 2D layers parallel to (001), between which the noncoordinating H2O molecules are sandwiched. The paramagnetic [Ni(H2O)2(phen)(C4H2O4)2/2] ⋅ 2H2O ( 2) obeys the Curie–Weiss law χm( T- θ) = 1.139cm3 ⋅ mol−1 ⋅ K with the Weiss constant θ = −0.95 K. [ABSTRACT FROM AUTHOR]

Abstract: Two adamantane-1,3-dicarboxylato bridged cobalt(II) phenanthroline complexes [Co2(H2O)2(phen)2(adc)2]·(C2H7N)·2H2O (1) and [Co(H2O)(phen)(adc)]·H2O (2) were synthesized in a mixed solvent under 45°C (H2adc=adamantane-1,3-dicarboxylic acid). Compound 1 consists of dinuclear [Co2(H2O)2(phen)2(adc)2] complex molecules, dimethylamine (C2H7N) molecules and hydrogen-bonded water molecules. The dinuclear molecules, via intermolecular hydrogen bonds, are interconnected into hydrogen-bonded chains along [100] and interdigitation of phen ligands due to interchain π⋯π stacking interactions assembles the hydrogen-bonded chains into 2D supramolecular layers parallel to (001). In compound 2, the Co(II) ions are bridged by adamantane-1,3-dicarboxylate anions to form 1D chains along [001], and the resulting chains are assembled into double-chains based on interchain π⋯π interactions. The double-chains are further held together via hydrogen bonds into 2D supramolecular layers parallel to (100). The variable temperature magnetic measurements show an overall weak antiferromagnetic behavior for 1, and an weak ferromagnetic behavior over 300–75K followed by antiferromagnetic behavior below 75K for 2. [Copyright &y& Elsevier]

Highlights: [•] 1 represents a rare topological example of 2D→3D interlocking systems. [•] 2 and 3 all exhibit a (3,4)-connected novel network topology. [•] The magnetic characterizations suggest π–π stacking interactions to be effective pathways. [Copyright &y& Elsevier]

Abstract: Three new phosphate-bridged copper(II) complexes, [Cu4(H2O)2(phen)4(μ4-PO4)2(μ2-O)]·11H2O (1), [Cu4(bpy)4(μ4-PO4)2(μ2-Cl)2]·18H2O (2) and [Cu2(bpp)4(H2PO4)2](HPO4)·H2O (3) (phen=1,10-phenanthroline, bpy=2,2-bipydine and bpp=1,3-bis(4-pyridyl)-propane), have been synthesized under ambient conditions. The tetranuclear Cu(II) butterfly cores in 1 are aggregated to 2D supramolecular layer via intermolecular π–π stacking interactions. In 2, the dinuclear copper units are bridged by the phosphate and Cl− anion to generate centrosymmetric tetranuclear complex molecules [Cu4(bpy)4(μ4-PO4)2(μ2-Cl)2], which are aggregated to 2D layers via π–π stacking interactions. The Cu atoms in 3 are interlinked by a pair of bpp ligands to generate 2D (4,4) network which is through twofold ‘2D parallel/2D parallel’ mode inclined interpenetration to induce 3D motifs. The variable temperature magnetic characterizations suggest antiferromagnetic coupling interactions with J =−9.38 and −28.03cm−1 for 1, J =−2.41cm−1 for 2, respectively. [Copyright &y& Elsevier]