Preparation, Crystal Structure and Magnetic Properties of Two 1,2-Di(4-pyridyl)ethylene-Bridged Manganese(II) Complexes

Two polymeric carboxylato-bridged manganese(II) complexes, $ {}_{\infty }^{1} $ ∞ 1 [Mn(bpe)(NBA)₂] (1) and $ {}_{\infty }^{1} $ ∞ 1 [Mn(bpe)(MBA)₂] (2) (bpe = 1,2-di(4-pyridyl)ethylene; HNBA = m-nitrobenzoic acid; HMBA = m-methyl-benzoic acid), were synthesized and characterized. Compounds 1 and 2 are isostructural. X-ray diffraction studies show that the title compounds possess a double chain structure. The chains in 1 and 2 are assembled into 2-D layers via C–H···O hydrogen bonds interactions. Furthermore, owing to the offset face-to-face π–π stacking interactions, the adjacent 2-D layers embed into each other to form a 3-D supramolecular framework. Variable-temperature (2–300 K) magnetic susceptibility measurements show the presence of weak antiferromagnetic interactions between the high-spin Mn(II) (S = 5/2) ions through a carboxylato bridge with the best fit parameters for 1 being J = ?0.13 cm^?1, zJ′ = ?0.098 cm^?1 and for 2, J = ?0.33 cm^?1, zJ′ = ?0.001 cm^?1.     

Preparation, Crystal Structures and Photoluminescence of Two New Zinc Complexes Based on 1H-Imidazo[4,5-f][1,10]-phenanthroline and Auxiliary Ligands

Two new coordination polymers [Zn(ip)(2,5-tda)(H₂O)₂] _n (1) and [Zn₂(ip)₂(5-npa)₂] _n (2) (2,5-tda = thiophene-2,5-dicarboxylic acid, ip = 1H-imidazo[4,5-f][1,10]-phenanthroline and 5-npa = 5-Nitroisophthalic acid) were synthesized and characterized by IR, elemental analysis, PXRD and X-ray diffraction. Single-crystal X-ray analyses revealed that 1 and 2 demonstrate a 1D chain structure. Complex 1 was bridged by 2,5-tda ligands in a μ₁ ? η¹:η⁰/μ₁ ? η¹:η⁰ coordination mode, and further extended into a 2D supramolecular structure by hydrogen bonding and π···π interactions. In 2, the 5-npa ligand acts as a bridging moeity, exhibiting μ₁ ? η¹:η¹/μ₁ ? η¹:η⁰ and μ₁ ? η¹:η⁰/μ₁ ? η¹:η⁰ coordination modes to link metal ions to form a 1D chain. The chains are further connected via hydrogen bonding interactions into a 2D supramolecular structure. The luminescent properties for 1 and 2 were investigated in the solid state at room temperature.     

1D Coordination Polymer from Tetraaza Macrocyclic Nickel(II) Complex and 1,2,3,4-Cyclobutanetetracarboxylic Acid

The self assembly of [Ni(L)]Cl₂·2H₂O (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,0^1.18,0^7.12]docosane) and 1,2,3,4-cyclobutanetetracarboxylic acid (H₄cbtc) acid generates a 1D coordination and 2D hydrogen-bonded polymer [Ni(L)(H₂cbtc)₂·3H₂O] _n (1). Complex 1 is characterized by X-ray crystallography, spectroscopy and magnetic susceptibility. Each nickel(II) ion has a distorted octahedral coordination environment with the four secondary amines of the macrocycle in which two carboxylate anions of the H₂cbtc^2? ligand have assembled around each nickel center. The compound crystallizes in the triclinic system P-1 with a = 9.715(3) Å, b = 12.891(5) Å, c = 13.903(6) Å, α = 72.64(2)°, β = 75.70(3)°, γ = 73.27(3)°, V = 1566.6(10) ų, Z = 2. The electronic spectrum of 1 indicates a high-spin octahedral environment. The magnetic behavior of 1 reveals a weak intramolecular antiferromagnetic interaction with J = ?1.23(1) cm^?1.     

Syntheses,Crystal Structures and Physical Properties of Four Zinc/Cadmium Coordination Polymers Based on 4-Nitrophthalic Acid and N-donor Auxiliary Ligands

Four new d¹⁰ metal coordination polymers, [Zn(4-NPA)(2,2-bipy)] _n (1), [Zn(4-NPA)(1,3-bimb)·H₂O] _n (2), [Cd(4-NPA)(2,2-bipy)] _n (3) and [Cd(4-NPA)(1,3-bimb)·H₂O] _n (4) (4-NPAH₂ = 4-nitrophthalic acid, 2,2-bipy = 2,2-bipyridine, 1,3-bimb = 1,3-bis(imidazol-1-ylmethyl)-benzene), have been hydrothermally synthesized and characterized by elemental analyses, IR spectra, and X-ray single crystal diffractions. Compounds 1?3 possess different one-dimensional (1D) chain structures. Compound 4 shows a two-dimensional (2D) layered structure. Moreover, the luminescent and thermal stabilities properties of compounds 1–4 were investigated in the solid state.     

Crystal Structures and Luminescent Properties of Two Lanthanide(III) Complexes Featuring Double-Stranded Helical Chains of Based on 2-Sulfoterephthalate

Hydrothermal reaction of Eu³⁺ and Dy³⁺ salts with monosodium 2-sulfoterephthalate (NaH₂stp) gives two 2D lanthanide coordination polymers, [Ln(stp)(H₂O)₂] _n (Ln = Eu (1) and Dy (2)). Single-crystal X-ray diffraction of the complexes reveal that both 1 and 2 crystallize in the triclinic crystal system of Pī space group. For 1, each Eu³⁺ ion lies in a 9-coordinated slightly distorted tri-capped triangle pyramidal configuration. The stp ligands adopt a μ ₄-type link to the metal ions to form a 2D layer-like structure, of which there exist the left- and right-handed double-stranded helical chains. For 2, each Dy³⁺ ion is in a 8-coordinated distorted bi-capped triangle pyramidal geometry. The double-stranded helical chains in 2 differ from those in 1. The thermal stabilities of the two compounds are studied by TGA. The solid state photoluminescence of 1 and 2 are reported. The fluorescent decay curves of the ligand and compounds indicate that 1 has the lifetime of 286.7 μs, τ ₁ = 0.51 ns and τ ₂ = 3.07 ns for the ligand, and for 2, τ ₁ = 0.53 ns and τ ₂ = 2.71 ns.     

A Novel 3-D Nanoporous Ce(III) Metal-Organic Framework with Terephthalic Acid; Thermal,Topology, Porosity and Structural Studies

This study describes the synthesis, crystal structure, porosity, and thermal stability of a new three-dimensional nano-porous metal-organic framework, [Ce₂(tp)₃(DMF)₂(DMSO)₂]_n, 1, (H₂tp = terephthalic acid, DMF = dimethyl formamid, DMSO = dimethyl sulfoxide). Compound 1 was synthesized by the solvothermal reaction of Ce(NO₃)₃·6H₂O and H₂tp and was then characterized by single-crystal X-ray diffraction and infrared spectroscopy. Structural analysis of 1 showed that Ce(III) ion has coordination number nine in a distorted mono-capped square anti-prismatic geometry. Gas sorption studies revealed a relatively reversible type-I isotherm characteristic of a porous material with surface area, pore volume, and average pore size of 179.4 m² g^?1, 0.73 cm³ g^?1, and 3.8 Å, respectively.     

Synthesis,Crystal Structures,Luminescence, Biological and Catalytic Properties of Two d10 Metal-Organic Coordination Polymers Constructed from Mixed Ligands

Two d¹⁰ metal-organic coordination polymers, [Cd₂(4-cpa)₄(bmip)₂]_n (1) and [Zn(4-cpa)₂(4,4′-bpy)]_n (2), [4-cpa = 4-chlorophenylacetate, bmip = 1,3-bis(2-methylimidazoly)propane, 4,4′-bpy = 4,4′-bipyridine], were hydrothermally synthesized and characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis (TGA), powder X-ray diffraction and single-crystal X-ray diffraction. Single-crystal X-ray diffraction studies indicated that both 1 and 2 display analogous wave-like infinite chain structures. The two coordination polymers are further extended into 3D supramolecular structures through π···π stacking interactions and C–H···O hydrogen bonds for 1 and π···π stacking interactions, C–H···π stacking interactions and C–H···O hydrogen bonds for 2. Both 1 and 2 emit the intense blue luminescence at room temperature. The 4-Hcpa ligand and complexes 1 and 2 have been screened for their herbicidal activities against Brassica napus L. and Echinochloa crusgalli L. The results are compared with the activity of quizalofop-P-ethyl. Both compounds exhibit high catalytic properties on degradation of methyl orange in Fenton-like process.     

A Series of Luminescent Lanthanide–Organic Complexes Constructed from In Situ Generated Dithiobenzoic Acid

Two types of lanthanide thiolato-carboxylate complexes, [Type I: [Yb(dtba) (Hdtba)] _n (1), Type II: [Ln(dtba)_1.5(biim)] _n (Ln = Pr (2a), Nd (2b), Sm (2c), Eu (2d), Gd (2e), Tb (2f), Dy (2g), H₂dtba = 2,2′-dithiodibenzoic acid, bimm = diimidazole)] have been obtained by hydrothermal method and characterized by the single-crystal X-ray diffraction, IR, 2D-COS IR, TG and the luminescence analysis. The H₂dtba ligand came from the in situ S–S function reaction of 2-mercaptobenzoic acid (H₂mba) under the hydrothermal condition. Complex 1 is a 2D bamboo-like sqr-topology layered structure, and the 3D (4, 4, 6)-connected supramolecular frameworks is produced by the hydrogen bonds of O–H···O. Complexes of type II (from 2a to 2g) are isostructural and they are assigned to 1D rope-like chains by introducing the chelating ligand of diimidazole. These 1D rope-like chains are further linked by N–H···O hydrogen bonds into a 3D supramolecular framework with CdSO₄-type topology. Photoluminescence studies reveal that complexes 2b, 2c, 2d, 2f, 2g exhibit strong lanthanide characteristic emission bands in the solid state at room temperature.     

Crystal Structures and Effect of Temperature on the Luminescence of Two Lanthanide Coordination Polymers with Twofold Interpenetrating pcu Topology

Two new lanthanide coordination polymers formulated as [Ln(BDC)_1.5(DMF)(H₂O)] _n [Ln = Tb (1), Gd (2)] [H₂BDC = 1,4-benzenedicarboxylic acid, DMF = N,N′-dimethylformamide] were synthesized under solvothermal conditions. The coordination polymers were characterized by IR spectroscopy, elemental analysis and X-ray single-crystal diffraction. The two coordination polymers are isostructural and exhibit twofold interpenetrating pcu three-dimensional open frameworks constructed by tetradentate ligand of H₂BDC. The fluorescence properties of 1 and 2 were investigated at 298 or 77 K both in solid state and in CH₂Cl₂ solvent dispersed as suspensions. Coordination polymer 1 exhibits characteristic Tb³⁺ ions emission transitions of ⁵D₄ → ⁷F _J (J = 6–2) at 77 or 298 K both in the solid-state and in CH₂Cl₂ solvent. Moreover, the vibrational structure of 1 is more defined at 77 K, which exhibits another two ⁵D₄ → ⁷F₁ and ⁵D₄ → ⁷F₂ transitions more than that at 298 K. The lifetimes of 1 are longer at 77 K (915.2 μs in the solid state and 874.11 μs in the CH₂Cl₂ solvent) than that at 298 K (866.31 μs in the solid state and 801.04 μs in the CH₂Cl₂ solvent), which may be caused by the increase of radiative rate and decrease of non-radiative rate at low temperature. The singlet excited state (28,653 cm^?1) and the lowest triplet energy level (23,641 cm^?1) of H₂BDC ligand were calculated based on the UV–Vis absorbance edges of ligand and the phosphorescence spectrum of Gd³⁺ coordination polymer (2) at 77 K, showing that the effective extent of energy transfer from H₂BDC ligand to Tb³⁺ ion. Finally, thermal behaviors of the two coordination polymers were studied by thermogravimetric analysis, which exhibit thermal stability to 250 °C.     

Syntheses, Structures and Properties of Two 2D Transition Metal Coordination Polymers Based on Oxalate and Two Types of N-donor Auxiliary Ligands

Two new two-dimensional (2D) metal–organic coordination polymers [Co(ox)(bbbm)]·H₂O (1) and [Cu(ox)(bppdca)]·2H₂O (2) (H₂ox = oxalic acid, bbbm = 1,1-(1,4-butanediyl)bis-1H-benzimidazole and bppdca = N,N′-bis(pyridin-3-yl)-2,6-pyridinedicarboxamide) were synthesized under hydrothermal conditions and structurally characterized. Both 1 and 2 exhibit a 2D four-connected network formed by the Co^II/Cu^II ions as four-connected nodes; and, the ox anions and bbbm/bppdca ligands as linkers with a (4⁴.6²) topology as determined by single crystal X-ray diffraction. In addition, the thermal stability, electrochemical and luminescent properties for 1 and 2 were investigated.     

Three New Coordination Polymers Constructed from Mixed Ligands: Syntheses,Luminescence and Magnetism

Three new coordination polymers, namely, {[Cd(H₂bptc)(IP)(H₂O)]·2H₂O} _n (1), {[Mn₂(IP)₂(dstc)]·6H₂O} _n (2) and {[Zn₂(IP)₂(dstc)]·3H₂O} _n (3) (IP = 1H-imidazo[4,5-f][1,10]-phenanthroline, H₄bptc = 3,3′,4,4′-benzophenonetetracarboxylic acid, and H₄dstc = 3,3′,4,4′-diphenylsulfonetetracarboxylic acid) have rationally designed and characterized by single crystal X-ray diffraction. Polymer 1 shows a 1D ribbon-like structure. Although compounds 2 and 3 feature 2D grid networks, the coordinative modes of dstc ligand and the arrangements of IP ligand are very different. Furthermore, the luminescence properties for 1 and 3, as well as the magnetism of 2 are explored in detail.     

Synthesis and Structural Characterization of Triorganotin(IV) Derivatives with 2,2′-Thiodiglycolic Acid and 3,3′-Thiodipropionic Acid

The synthesis and structural characterization of four novel triorganotin(IV) complexes, {(R₃Sn)₂[C₂H₄S(COO)₂]} _n (R = Me: 1), {(R₃Sn)₄[C₂H₄S(COO)₂]₂} _n (R = nBu: 2), {(R₃Sn)₂[C₄H₈S(COO)₂]} _n (R = Me: 3; nBu: 4) were obtained by the reaction of 2,2′-thiodiglycolic acid, 3,3′-thiodipropionic acid and the corresponding R₃SnCl (R = Me, nBu) with potassium hydroxide in methanol. All the complexes were characterized by elemental analysis, Fourier transform infrared and nuclear magnetic resonance (¹H, ¹³C, ¹¹⁹Sn) spectroscopies, X-ray crystallography and thermogravimetric analyses. The crystal structures show that 1 has 2D network structure in which 2,2′-thiodiglycolic acid acts as a tetradentate ligand coordinating to the trimethyltin(IV) ions. Complexes 2, 3, and 4 are 3D metal-organic framework structures in which the deprotoned acids act as a tetradentate ligand afforded by four oxygen atoms.     

Structure,Luminescence, and Vapochromism of Bridged Cationic Copper(I) Dimers and Polymers

The dimeric complex of Cu(I) [Cu₂(PPh₃)₄(MeCN)₂(Bpy)](BF₄)₂ (1a, Bpy = 4,4′-dipyridyl) self-assembles in CH₂Cl₂ or acetone and shows intense photoluminescence (excitation λ_max = 356 nm, emission λ_max = 486 nm, ? = 0.47). The MeCN ligands are readily removed from 1a, producing [Cu₂(PPh₃)₄(Bpy)](BF₄)₂ (1b) and altering the photophysical behavior (excitation λ_max = 336 nm, emission λ_max = 568 nm, ? = 0.07). The desolvated compound 1b reversibly absorbs many vapor phase nucleophiles, as revealed by thermogravimetry. Intense luminescence emission is restored for 1b/Nu, Nu = MeCN (1a), acetone, tetrahydrothiophene (THT), and Et₂S. Films of 1b are produced when CH₂Cl₂ solutions of 1a are cast onto glass. The films also react with Nu vapor, again producing intense emission. The pyrazine-bridged dimer [Cu₂(PPh₃)₄(MeCN)₂(Pyz)](BF₄)₂ (2a) is produced in CH₂Cl₂, while [Cu₂(PPh₃)₄(MeCN)(acetone)(Pyz)](BF₄)₂?½[Cu₂(PPh₃)₄(MeCN)₂(Pyz)](BF₄)₂ (2b) is formed in acetone. The crystal structure of the polymer {[Cu(PPh₃)₂(Bpy)](BF₄)?acetone} _n (3) is reported, as is the mixed polymer/dimer structure {[Cu(PPh₃)₂(Pyz)](BF₄)} _n ?½n[Cu₂(PPh₃)₄(BF₄)₂(Pyz)] (4b) in which the dimer units show Cu–FBF₃ coordination. The Pyz dimer and the Pyz and Bpy polymers show much weaker luminescence behavior than that of Bpy dimers 1a and the related 1b/Nu adducts. Nucleophile adduct structures [Cu₂(PPh₃)₄(THT)₂(Bpy)](BF₄)₂?½ethyl ether (5) and [Cu₂(PPh₃)₄(Py)₂(Bpy)](BF₄)₂?CH₂Cl₂ (6) confirmed the coordination of one Nu per Cu to 1b.     

Synthesis, Crystal Structures and Fluorescence Properties of Two One-Dimensional Cadmium(II) Coordination Polymers Containing Flexible Bis(benzimidazole) Ligands

Two one-dimensional Cd(II) coordination polymers constructed by ribbon-like molecules, {[Cd(L₁)₂(NO₃)]·NO₃} _n (1) (L₁ = 1,3-bis(5,6-dimethylbenzimidazol-1-yl)benzene) and [Cd(L₂)₂(NO₃)₂] _n (2) (L₂ = 1,3-bis(benzimidazol-1-yl)benzene) have been obtained through assembly of the two structurally similar flexible bis(benzimidazole)-based ligands and cadmium nitrate tetrahydrate. The cadmium(II) centers display different coordination environments with trigonal-bipyramidal geometry in 1, and a octahedral geometry in 2. Weak C–H···O interactions in 1 result in a two-dimensional supramolecular layer; two π–π interactions are present in 2 forming a three-dimensional supramolecular network structure. The solid state fluorescence properties of 1 and 2 were investigated.     

Hydrothermal Synthesis, Crystal Structures and Photoluminescent Properties of Two New Co(II) Coordination Polymers Derived from Dicarboxylate and N-Donor Ligands

Two new Co(II) coordination polymers with 5-position substituted 1,3-benzenedicarboxylate and N-donor auxiliary ligands, [Co(5-OH-ip)(L₁)_1.5(H₂O)]_n (1) and [Co(5-NO₂-ip)(L₂)_1.5]_n (2) (5-OH-ip = 5-hydroxyisophthalic acid, 5-NO₂-ip = nitroisophthalic acid, L₁ = 1,4-bis(imidazol-1-yl) benzene and L₂ = 1,4-bis(1-imidazol-yl)-2,5-dimethyl benzene), were synthesized by hydrothermal reactions. Complex 1 shows a 3-fold interpenetrating 3D framework with the topological symbol of (4⁴·6⁶). Complex 2 exhibits a 3D framework with the vertex symbol of (4²·6⁸). Furthermore the luminescent properties of 1 and 2 were investigated.     

Synthesis, Crystal Structures and Properties of Two Metal–Organic Frameworks Constructed from Pyridine Dicarboxylate and Flexible Bis(imidazole) Ligand

Two novel interesting metal–organic frameworks, [Zn(PDA)(bbi)] _n (1) and [Cd₂(PDA)₂(bbi)₂(H₂O)₂·10H₂O] _n (2) [H₂PDA = pyridine-2,6-dicarboxylic acid, bbi = 1,1′-(1,4-butanediyl)bis(imidazole)] have been isolated under hydrothermal conditions and structurally characterized. X-ray single crystal structure analysis reveals that complex 1 crystallize in monoclinic P2₁/c space group, while complex 2 crystallize in triclinic P-1 space group. The PDA^2? anions act in two different coordination modes: terminal chelating for 1 and chelating and bis-monoatomic bridging for 2. Polymeric chains of 1 and 2 are composed of Zn(II) and Cd(II) ions bridged by bbi ligands. The fluorescent properties of 1 and 2 were also investigated.     

Completely Isospecific Polymerization of 1-Hexene Catalyzed by Hafnium(IV) Dichloro Complex Incorporating with an [OSSO]-type Bis(phenolate) Ligand

In the presence of dried methylaluminoxane as an activator, the hafnium(IV) dichloro pre-catalyst 4 incorporating with an [OSSO]-type ligand was found to promote precisely isospecific 1-hexene polymerizations of [mmmm] up to 95 % with fairly high activities (1,050–3,180 g mmol(4)^?1 h^?1) and relatively narrow polydispersities (M _w/M _n = 1.5–1.8).     

Hydrothermal Syntheses and Crystal Structures of Three Complexes Constructed with Dipyrido[3,2-a:2′,3′-c]phenazine and 2,4′-Biphenyldicarboxylic Acid

Three new metal complexes, [Pb(dppz)(2,4′-bpdc)] _n ·n(H₂O) (1), [Fe(dppz)(2,4′-bpdc)(H₂O)] _n (2) and [Cu(dppz)(2,4′-bpdc)(H₂O)] _n (3) (2,4′-H₂bpdc = 2,4′-biphenyldicarboxylic acid and dppz = dipyrido[3,2-a:2′,3′-c]phenazine), have been synthesized and characterized by elemental analysis, IR, X-ray single-crystal diffraction and powder X-ray diffraction. The complexes 1, 2 and 3 have 1D chains formed via coordination bonds, and unique three-dimensional or two-dimensional supramolecular structures are further formed due to π–π stacking interactions. The results reveal that the coordination preferences of metal ions play a critical role in the framework construction of these complexes. Meanwhile, the thermogravimetric analysis and photoluminescent property of compounds 1–3 have also been investigated.     

Synthesis, Crystal Structures and Luminescent Properties of pH-Dependent Zn (II) Coordination Polymers

Two new coordination polymers [Zn(L)(bib)] _n (1) and [Zn(L)(bib)_0.5] _n (2) [L = 5-hydroxyisophthalic acid and bib = 1,4-bis(2-methyl-imidazol-1-yl)butane] have been synthesized and characterized. X-ray single crystal diffractions show that complex 1 is a 2D layered structure and complex 2 is a 3D 6-connected topological net. Complex 1 are further assembled into a 3D supramolecular structure by intermolecular hydrogen bonding. Complex 2 features a two-fold interpenetrated pcu topology. Moreover, the fluorescent properties of complexes 1 and 2 were studied in the solid state at room temperature.     

1D Ladder-Like Structure Motif Assembled from Edge-Sharing Rhombic Squares of Sm2Mo2 Based on [Mo(CN)8]4− and Sm3+ Ions as Building Blocks

Novel bimetallic 4d–4f complex, {Cs[Sm(MeOH)₃(DMF)(H₂O)Mo(CN)₈] · H₂O} _n (1) (DMF = N,N′-dimethylformamide) has been synthesized and structurally characterized. The crystal analyses shown that 1 exhibit a one-dimension (1D) infinite chain structure, which adopts a 1D ladder-like structure motif assembled from edge-sharing rhombic squares of Sm₂Mo₂, and that is the first structurally characterized example of a 1D ladder structure based on the [Mo(CN)₈]^4? and Sm³⁺ building blocks. The complex 1 crystallizes in triclinic, space group P-1, with a = 9.905(2), b = 10.333(2), c = 13.562(3) Å, α = 82.00(3)°, β = 86.62(3)°, γ = 65.76(3)°, V = 1253.5(4) Å³ and Z = 2. The magnetic behavior of 1 has also been studied in this paper.