Hydrothermal synthesis, crystal structure of two new coordination polymer {[Ni2(Imazameth)2(4,4′-Bipy)] · (ClO4) · CH2OH · H2O} n and [Cu2(PDA)1.5(2,2-Bipy)2](H2O)5(NO3)

Two new metal-organic coordination polymers framework formulated as [Cu₂(PDA)_1.5(2,2′-Bipy)₂](H₂O)₅(NO₃) (I) and {[Ni₂(Imazameth)₂(4,4′-Bipy)] · (ClO₄) · CH₂OH · H₂O _n (II), where H₂PDA = 1,4-phenylenediacetic acid, 2,2′-Bipy = 2,2′-bipyridine, Imazameth = (+/?)2-(4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl)-5-methyl-3-pyridinecarboxylic acid, 4,4′-Bipy = 4,4′-bipyridine, have been prepared and characterized by spectral method (IR), elemental analysis and single crystal X-ray diffraction techniques. Complex I consists of one-dimensional ladder-like chains featuring binuclear unit in which the two Cu²⁺ ions have different coordination geometry: one is five-coordinated, the other is six-coordinated. Complex II is a new two-dimensional copper complex with the peculiarity of having the 4,4′-Bipy ligand and Imazameth ligand acting as bridge to form planar network polymer. Both I and II exist abundant hydrogen bonds. It is result in the formation of a supermolecular crystal, in which they seem to be effective in the stabilization of the structure.     

A 1D double chains architecture based on the pyridine-2-sulfonate, 4,4′-Bipyridine and acetate-bridged of Zn(II) complex: Synthesis, spectral, thermal properties, and crystal structure

A new 1D double chains Zn(II) supramolecule framework, {[Zn₂(2-pSO₃)₂(Ac)₂(4,4??-Bipy)₂](4,4??-Bipy)} _n (I) (2-pSO₃H = pyridine-2-sulfonate, 4,4??-Bipy = 4,4??-bipyridine), was synthesized by reaction of Zn(CH₃COO)₂ · 2H₂O in methanol-water mixed solution and characterized by X-ray diffraction, elemental analysis, and IR spectrum. X-ray analysis indicates that I is a coordination polymer in which two deprotonated 2-pSO₃H through the aromatic nitrogens in trans positions, oxygens in cis positions and two N atoms of 4,4??-Bipy and two ??₂-Ac^? ligands, resulting in a ZnN₃O₃ distorted octahedral geometry. The 1D coordination polymer was connected to 2D and 3D supramolecule framework via ??-stacking and weak C-H??O contacts. The complex I also displays strong fluorescence property and good thermal stability.     

Two naphthoate-based lead(II) complexes with different limited-nuclear motifs: Syntheses,crystal structures,and fluorescent properties

Two new naphthoate-based lead(II) complexes, [Pb(NA)₂(2,2’-Bipy)] (I) and [Pb₂(NA)₄(4,4’- Bipy)] (II) (NA–= 1-naphthoate, 2,2’-Bipy = 2,2’-bipyridine, and 4,4’-Bipy = 4,4’-bipyridine) (CIF files CCDC nos. 664900 (I), 664899 (II)) have been hydrothermally synthesized by varying the N-heterocyclic coligands. Structural analyses reveal that the two complexes possess different limited-nuclear motifs, the former one owns mononuclear unit and the last complex exhibits centrosymmetric binuclear motif bridged by 4,4’-Bipy connector. The coordination numbers of Pb(II) metal centers in I and II are four and five, respectively. The NA^– anions in both complexes show the same binding modes, it is obvious that the bipyridyl coligands in the present mixed-ligands system are responsible for the dissociation or dimerization of mononuclear structural units and the binding numbers of the metal ion. In both complexes, the 6s lone pair of electrons of Pb²⁺ has a stereochemistry activity resulting the distribution of the Pb–O and Pb–N bonds in a hemisphere. Furthermore, both of the two compounds are linked to 2D network by intermolecular C–H···O hydrogen bonding and π···π stacking interactions, exhibiting strong fluorescent emissions resulting from the NA^?-based intraligand charge transfer at room temperature, which can be hopefully used as fluorescent materials.     

Synthesis,characterization, and crystal structure of one zinc(II) complex with 4-Hydroxypyridine-2,6-Dicarboxylic acid and 4,4′-bipyridine

A new zinc(II) coordination polymer, {[Zn(HCAM)(4,4′-Bipy)_0.5] · H₂O} _n (I) (H₃CAM = 4-hydroxypyridine-2,6-dicarboxylic acid; 4,4′-Bipy = 4,4′-bipyridine), has been synthesized by hydrothermal reaction of Zn(OAc)₂, H₃CAM and 4,4′-Bipy. It has been structurally characterized by element analysis, IR-spectra. X-ray single-crystal analysis was carried out for I (CIF file CCDC no. 974199), which crystallizes in the orthorhombic system, space group Pbca. The single X-ray diffraction studies reveal that I shows a new 2D wave-like plane with 3-connected net. Furthermore, the thermal stability of compound I was studied.     

Hydrothermal synthesis, crystal structures, and properties of two Co(II) complexes based on 4-bromoisophthalic acid and N-donor ligands

Two new Co(II) complexes, [Co₂(H₂O)(Bipy)₂(Bript)₂] _n (I) and [Co(H₂O)(Phen)(Bript)] · H₂O (II), where H₂Bript = 4-bromoisophthalic acid, Bipy = 2,2??-bipyridine, and Phen = 1,10-phenanthroline, have been synthesized and characterized by elemental analysis, IR, and single-crystal X-ray diffraction. Complex I has binuclear units in which two Co²⁺ ions are bridged by two carboxylate groups and a coordinaiod-water molecule, and the binuclear units are connected by Bript to generate a 1D helical chain. These 1D helical chains are further linked by ????? stacking interactions to form a 3D supramolecular network, while complex II has a 2D layer motif. In I and II, there exists extensive hydrogen bonding interactions. The thermal behavior of the two corresponding complexes have briefly been investigated.     

Three one-dimensional chains with bulky backbone carboxylate ligands: Syntheses,crystal structures,and luminescent properties

To explore the influence of bulky backbone on complexes, three Co(II) and Zn(II) complexes with phenanthrene-9-carboxylate (L¹), 9H-fluorene-9-carboxylate (L²) or biphenyl-4-carboxylate (L³) together with incorporating auxiliary bridging ligad 4,4′-bipyridine (4Bipy), were synthesized and characterized: [Co(L¹)₂(4Bipy)(H₂O)₂]_∞ (I), [Zn(L²)₂(4Bipy)_0.5(4Bipy)_0.5]_∞ (II), and [Zn₃(L³)₄(4Bipy)_0.5(4Bipy)_0.5(4Bipy)_0.5(OH)₂]_∞ (III). X-ray single-crystal diffraction analyses show that complexes I–III both assume one-dimensional (1D) structures by incorporating the bridging 4Bipy (CIF file CCDC nos. 942729 (I), 942727 (II), and 942733 III). In I, mononuclear six-coordinated Co²⁺ ions are linked into a 1D linear chain by 4Bipy. While in II, mononuclear four-coordinated Zn²⁺ ions are linked into a 1D zigzag chain by 4Bipy. But in III, because of the existence of OH^?, hexanuclear Zn(II) can be regarded as a node, then bridge adjacent hexanuclear Zn(II) nodes by almost parallelled three 4Bipy ligands into a 1D linear chain. Finally the 1D chains of I–III are further assembled into an overall three-dimensional (3D) framework via intermolecular H-bonding, π…π stacking, and/or C-H…π supramolecular interactions, respectively. The results indicate that, besides different metal ions Co²⁺ and Zn²⁺ or OH^? anions, the steric hindrance of backbone ligands play an important role in the formation of I–III. Moreover, the luminescent properties of corresponding ligands and their complexes were briefly investigated.     

Design and synthesis of two-dimensional pillared MOF layers by connecting infinite one-dimensional chains via 4,4′-bipyridine

Two novel metal-organic frameworks, [Cd(Bna)(DMF)₂(H₂O)₂] _n · nDMF (I) (Bna = 2,2′-dihydroxy-l,l′-dinaphthyl-3,3′-dicarboxylate) and [Cd(Bna)(Bipy)(DMF)₂] _n (II) (Bipy = 4,4′-bipyridine) have been synthesized under mild conditions and structurally characterized. Crystal structural analyses reveal that complex I adots a 1D spiral structure with DMF guest molecules in the spiral by hydrogen bondings. Complex II is constructed by -Cd-Bna-Cd- zigzag chains, which are further connected by Bipy into a 2D sheet. X-ray powder diffraction and thermogravimetric analyses for I and II show that they are highly themally stable in the solid state.     

Hydrothermal synthesis, crystal structure, and photoluminescence of a new 2D cadmium(II) complex: {Cd(C8H5O3Cl2)2(C10H8N2)} n

One new cadmium coordination polymer, [Cd(2,4-Dcp)₂(4,4-Bipy)] _n (I) (2,4-HDcp = 2,4-dichlorophenoxyacetic acid, 4,4′-Bipy = 4,4′-bipyridine) with 2D layer structure, has been prepared by the hydrothermal synthesis and characterized by elemental analysis, IR, TGA and single-crystal X-ray diffraction. Complex I crystallizes belong to monoclinic system and has C2/c space group. Each Cd²⁺ ion is six-coordinated and located at an octahedral geometry. The Cd²⁺ ions are linked by bidentate 2,4-Dcp groups into a linear chain in which the benzene rings of 2,4-Dcp ligands point alternately up and down. These chains are further connected into a sandwich-like layer though 4,4′-Bipy ligands. Furthermore, the photoluminescence and life-time of I in the solid state have been studied.     

Complexes built with a scorpion-type tripodal ligand and metal ions: syntheses, structural features, electrochemical properties and magnetic properties

The complexes [Fe(bpz*mpy)₂](ClO₄)₂ (1a), [Cu(bpz*mpy)₂](ClO₄)₂ (1b) and [Ag(bpz*mpy)(Ph₃P)](ClO₄) · H₂O (2) (bpz*mpy = pyridin-2-yl-bis(3,5-dimethylpyrazol-1-yl)methane) have been synthesized and characterized by physicochemical and spectroscopic methods. X-ray crystallographic analysis reveals that the central Fe^II and Cu^II ions in complexes 1a and 1b are located on a twofold rotation axis and have a distorted octahedral coordination sphere, while the Ag^I center in complex 2 is tetrahedrally coordinated. The electrochemical properties of complex 1b have been investigated. Furthermore, a variable temperature magnetic susceptibility study of complex 1a has also been performed over the measured temperature range 2–300 K.     

A new 2D Mn(II) coordination polymer constructed from carboxylate and N-donor coligand: Synthesis,structure, and magnetism

A new complexes, namely, {[Mn₂(L)₂(Bipy)₂] · H₂O} _n (I) (H₂L = diphenic acid, Bipy = 4,4′-bipyridine) has been synthesized and structurally characterized by single-crystal diffraction analysis. In I, the two syn, anti-carboxylate groups in L bridge Mn(II) forming a one-dimensional chain, which is further connected by Bipy into 2D double layer. Magnetic study reveals the overall antiferromagnetic interaction between neighboring Mn²⁺ ions in compound I.     

Hydrothermal synthesis, crystal structure, and properties of two novel binuclear complexes based on Zaltoprofen and 2,2′-bipyridine ligands

Two novel binuclear metal-organic coordination complexes [M₂(Zaltoprofen)₂(Bipy)₂] [M = Cd (I), Zn (II); Zaltoprofen = 5-(1-carboxyethyl)-2-(phenylthio)phenylacetic acid, Bipy = 2,2′-bipyridine) have been synthesized under hydrothermal conditions and characterized by single crystal X-ray diffraction, elemental analysis, IR and electronic spectroscopy, powder X-ray diffraction, and fluorescent properties. Complexes I, II crystallize isomorphously in the monoclinic space group P2₁/c. Structural analysis shows that the M(II) atom of I and II is coordinated with four oxygen atoms from the carboxyl group of the Zaltoprofen together with two nitrogen atoms from the Bipy. The 3D structures of the complexes are stabilized by π-π stacking interactions.     

Crystal structures and electrochemical properties of two Mn(II) 2-sulfoterephthalate complexes with N-donor ligands

Two Mn(II) sulfoterephthalate complexes, [Mn(HStp)(o-Phen)₂] (I) and [Mn(HStp)(2,2′-Bipy)₂] (II) (H₃Stp = 2-sulfoterephthalic acid, o-Phen = 1,10-phenanthroline, 2,2′-Bipy = 2,2′-bipyridine), were synthesized under hydrothermal condition. Single crystal X-ray diffraction analyses reveal that complexes I and II possess similar structure, in which the center Mn²⁺ ions are hexa-coordinated with one Hstpanion and two N-donor ligands. For both of them, the formation of 3D supramolecular structures are based on both H-bonds and π...π/C-H...π stacking interactions. Electrochemical properties of complexes I and II have been investigated by means of cyclic voltmetry, which shows that electron transfer between Mn(III) and Mn(II) in electrolysis is quasi-reversible process.     

Novel 1D Mn(II) complexes containing aromatic dicarboxylic acids

Three Mn(II) complexes of [MnL(Bipy)(H₂O)] _n (I), [Mn₃(Phen)₂(HL)₂(L)₂]n (II), and [Mn(Phen)₂(HL)(OH)] (III), where L = 4,4′-(2-acetylpropane-1,3-diyl)dibenzoic acid, Bipy = 2,2′-bipyridine, and Phen = 1,10-phenanthroline, were hydrothermally synthesized and characterized by single crystal X-ray diffractions, infrared spectroscopy, thermogravimetric analyses, and magnetic analyses. Complexes I and II are one dimensional (1D) coordination polymers which can form the supramolecules with the help of the intermolecular hydrogen bond interactions. Finally, the landé factors are simulated by magentochemical analysis to be 2.15 and 1.80 for I and II with S = 5/2, respectively.     

Construction of a new one-dimensional Hg(II) coordination polymer [Hg4(Chbz)4(4,4′-Bipy)2(NO3)4 · H2O] n involving in situ chlorobenzene synthesis

A new 1D Hg(II) coordination polymer, [Hg₄(Chbz)₄(4,4′-Bipy)₂(NO₃)₄ · H₂O] _n (I) (Chbz = 2-chlorophenyl, 4,4′-Bipy = 4,4′-bipyridine), has been synthesized by the in situ synthesis of 2-chlorophenyl from the reaction of 2-chlorobenzoic acid, 4,4′-Bipy and mercury salt under hydrothermal conditions and characterized by elemental analysis, IR, TGA and single-crystal X-ray diffraction. Complex I exhibits an interesting 1D infinite zigzag polymeric chain along the x axis. The photoluminescent measurements reveal that complex I exhibits fluorescent emission in the solid state at room temperature.     

Hydrothermal synthesis and structural characterization of a new one-dimensional ladder-shaped metal-organic framework Zn(HTci)(4,4′-bipy)0.5 · H2O (H3Tci = tri(2-carboxyethyl)isocyanurate, 4,4′-bipy = 4,4′-bipyridine)

A new metal-organic coordination polymer, namely, Zn(HTci)(4,4′-Bipy)_0.5 · H₂O (I) (H₃Tci = tri(2-carboxyethyl)isocyanurate, 4,4′-Bipy = 4,4′-bipyridine), has been synthesized under hydrothermal conditions by the reaction of zinc nitrate, H₃Tci, and 4,4′-Bipy with the presence of H₂O and characterized by elemental analysis, IR and X-ray single-crystal diffraction. The X-ray diffraction analysis reveals that I crystallizes in the triclinic system, $P\bar 1$ space group. The unit cell parameters for I: a = 5.248(1), b = 12.537(2), c = 14.597(2) Å, α = 91.91(1)°, β = 91.22(2)°, γ = 95.75(1)°, V = 954.8(3) ų, Z = 2.     

Mixed-ligand complexes based on asymmetric gadolinium β-diketonates: Synthesis, crystal structure, and theoretical modeling

Mixed-ligand complexes of asymmetric gadolinium β-diketonates with 2,2′-bipyridyl (Bipy)—[Gd(Pa)₃(Bipy)] (HPa is pivaloylacetone) (I) and [Gd(Pta)₃(Bipy)] (HPta is pivaloyltrifluoroacetone) (II)-have been obtained by direct interaction of initial reagents and their structures have been studied by X-ray crystallography. Crystals of I are monoclinic: a = 9.536(1) Å, b = 15.037(1) Å, c = 13.280(1) Å, β = 109.56(1)°, V = 1798.7(3) ų, Z = 2, space group P2₁. Crystals of II are triclinic: a = 9.6696(17) Å, b = 12.1348(9) Å, c = 18.243(3) Å, α = 100.257(12)°, β = 103.997(2)°, γ = 101.438(11)°, V = 1977.4(5), Z = 2, space group P $\bar 1$ . The coordination polyhedron of the central gadolinium atom in I and II is a distorted square antiprism formed by six oxygen atoms of the three β-diketonate ligands (av. Gd-O, 2.35(2) and 2.351(5) Å in I and II, respectively) and two nitrogen atoms of the Bipy ligand (av. Gd-N, 2.47(2) and 2.584(7) Å in I and II, respectively). Although the molecular structures of these complexes are similar, they have different crystal packings. In II, the planes of the Bipy ligands of neighboring molecules related by an inversion center are bound by stacking interaction (the distance between the Bipy planes is 3.45 Å). The structure and properties of these mixed-ligand complexes have been discussed based on the results of quantum-chemical density functional theory calculations (DFT/B3PW91). The nature of the substituents in the β-diketonate ligand has an effect on the structure and properties of the complexes. The correlation between the Gd-Dik and Gd (Dik)₃-Bipy bond energies has been studied.     

Dipyridyl-type ligand-directed assembly of three cobalt(II) coordinated polymers based on carboxyphenylpropionate

A series of Co(II)-H₂Cpp coordination polymers incorporating different auxiliary ligands, [Co(Cpp)(Phen)(H₂O)] (I), {[Co(Bipy)(H₂O)₄](Cpp)} _n (II), and [Co(Cpp)(Bds)(H₂O)] _n (III) (H₂Cpp = 3-(4-carboxyphenyl)propionic acid, Phen = 1,10-phenanthroline, Bipy = 4,4′-bipyridyl, and Bds = 4,4′-bipyridyl sulfide), were synthesized by the hydrothermal reaction and characterized by single crystal X-ray diffraction, elemental analysis, IR, and TG. Three complexes display from 0D to 1D different structural features under the regulation of distinguishing dipyridyl-type coligands. Complex I possesses a binuclear Co(II) motif constructed by H₂Cpp and Phen, which further developing a zipper-like 2D layer via H-bonded and π-π stacking interactions. Complex II displays straight Bipy-bridging 1D chain, and further forming a 3D supramolecular structure by hydrogen-bonded interactions. Complex III exhibits 1D double-chain collectively jointed by Cpp and Bds, which further interlinked into a 3D supramolecular architecture by H-bonded interactions.     

Syntheses,structures, magnetic properties,and photoluminescence of compounds Ln(2,2′-Bipy)(C4H8NCS2)3 · 0.5CH2Cl2 (Ln = Sm,Eu, Tb,Dy, and Tm)

Five compounds of the composition Ln(2,2′-Bipy)(C₄H₈NCS₂)₃ · 0.5CH₂Cl₂ (Ln = Sm (I), Eu (II), Tb (III), Dy (IV), and Tm (V); 2,2′-Bipy = 2,2′-bipyridine) are synthesized. According to the X-ray diffraction data (CIF file CCDC 986259), the crystal structure of compound I consists of molecules of the mononuclear complex [Sm(2,2′-Bipy)(C₄H₈NCS₂)₃] and solvate molecules CH₂Cl₂ (2 : 1). The coordination polyhedron N₂S₆ of the Sm atom is a distorted tetragonal antiprism. The X-ray diffraction analysis shows that compounds I–V are isostructural. The magnetic properties of compounds I–V are analyzed in the temperature range from 2 to 300 K. At 300 K compounds I and III are photoluminescent in the visible spectral range. The photoluminescence intensity of compound I considerably exceeds that of complex III.     

Synthesis, crystal structures, and properties of inorganic-organic hybrid complexes constructed from copper(II) macrocyclic fragment

Reaction of a macrocyclic copper(II) complex [Cu(L)](ClO₄)₂ · 3H₂O (I) (L = 1,3,10,12,16,19-hexaazatetracyclotetracosane) with a hexapod carboxylate ligand H₆TTHA (H₆TTHA = 1,3,5-triazine-2,4,6-triamine hexaacetic acid) and a tripod carboxylate ligand H₃TATB (H₃TATB = 4,4′,4″-S-triazine-2,4,6-triyl-tribenzoic acid) yielded two mononuclear copper(II) complexes [Cu(L)][H₄TTHA] · 4H₂O (II) and [Cu(L)][HTATB] · 4H₂O (III). The complexes I–III have been structurally characterized. The crystal structures of complexes II and III show the copper(II) ion has a distorted pentacoordinate square-pyramidal geometry with two secondary and two tertiary amines from the macrocyclic complex [Cu(L)]²⁺ and one oxygen atom from the carboxylate ligand group at the axial position. The UV-Vis spectra are utilized to discuss the hydrolysis of the complex II.     

Manganese(II) and copper(II) complexes based on pentafluorobenzoate: interaction of fluorine in solid state

The synthesis and characterization of Mn(II) and Cu(II) complexes with the general formula [Mn(Phen)₂(Pfbz)₂](Hpfbz) (I) and [Cu₂(Bipy)₂(Pfbz)₄] (II) (Phen = 1,10-phenanthroline, Bipy = 2,2′-bipyridine, Pfbz = pentafluorobenzoate) are reported. I crystallizes in triclinic crystal system, space group {tiP}1 with a = 9.755(1), b = 11.302(1), c = 20.064(2) Å, α = 95.799(2)°, β = 90.176(2)°, γ = 113.993(2)°, and Z = 2. Complex II crystallizes in triclinic crystal system, space group P1 with a = 9.661(1), b = 9.951(1), c = 12.891(1) Å, α = 102.943(2)°, β = 98.972(2)°, γ = 96.746(2)°, and Z = 1. Of particular interest, intricate C-H…F and F…F interactions in the two crystals play important role in the formation of three dimensional supramolecular networks. F(lp)…π (lp = lone pair) interaction is recognized in the solid-state structure of II.