The synthesis and crystal structure of [M{H2B(tz*)2}2(H2O)] (M=Cu,Zn and tz*=3,5-dimethyl-1,2,4-triazole)

New ligand [KH₂B(tz^*)₂] (tz*=3,5-dimethyl-1,2,4-triazolyl) has been synthesized and the reactions of two different metal salts (copper and zinc) with the new ligand in agar gave two similar crystalline polymorphic forms: [Cu{H₂B(tz^*)₂}₂(H₂O)] (1) and [Zn{H₂B(tz^*)₂}₂(H₂O)] (2). A single crystal X-ray study revealed that the compound 1 was the monoclinic system with space group C2/c and a=8.462(3) Å, b=14.039(6) Å, c=19.991(8) Å, β=94.622(7)°, Z=4, R₁=0.0451, wR₂=0.1110. And the compound 2 was the monoclinic system with space group C2/c and a=8.4214(4) Å, b=13.8765(7) Å, c=20.2969(6) Å, β=95.615(2)°, Z=4, R₁=0.0667, wR₂=0.1375. The metal(II) ion in the complex is five-coordinated with four nitrogen atoms which come from triazolyl and one oxygen atom which come from water molecular. In both compounds, the hydrogen atoms of water molecule are connected by hydrogen bonding with N atoms of two adjacent complex molecules to form 2-D planes. The spectroscopic results are consistent with the crystallographic study.     

A novel two-dimensional chiral coordination polymer: bis(S-(-)-lactate)zinc(II)

The synthesis and X-ray characterization of a novel chiral two-dimensional condensed metal–organic coordination polymer, bis(S-(-)-lactate)zinc(II) (1), are reported. Its crystal structure determination shows that a chiral cavity with approximate dimensions of 5.4×5.4 Ų is present. Crystallographic data for 1, C₆H₁₀O₆Zn, monoclinic P2₁, a=7.4440(15), b=7.4550(15), c=7.4550(15) Å, β=95.73(3)°, V=429.48(15) ų, R₁=0.0272, wR₂=0.0751.     

Lanthanide(III) 1,4-Phenylenediacetate Complexes: The Relation Between the Structure and Thermal Properties

The series of isostructural lanthanide coordination polymers with the empirical formula [Ln₂(PDA)₃(H₂O)]·2H₂O, where PDA = 1,4-phenylenediacetate anion = [C₈H₈(COO)₂]^2?; Ln = La-Lu(III), and Y(III) were produced in the reaction of LnCl₃·nH₂O with ammonium salt of 1,4-phenylenediacetic acid in water solution. The compounds were characterised structurally using powder X-ray diffraction, elemental and thermogravimetric analyses as well as FT-IR spectroscopy. Thermogravimetric analyses show that in the range 60–170 °C the dehydration process occurs. The thermal stability of dehydrated compounds, Ln₂(PDA)₃ increased from about 200–350 °C in the whole series of complexes. Single-crystal X-ray diffraction analysis for the Gd(III) complex revealed that the compound crystallizes in the monoclinic P2₁/c space group with a = 21.863(2) Å, b = 10.035(1) Å, c = 13.854(1) Å, β = 91.53(1)° and V = 3,038.5(4) ų. The complex contains one-dimensional gadolinium-carboxylato chains, which are connected with the –CH₂–C₆H₄–CH₂– spacers of PDA ligand to the three-dimensional metal–organic framework.     

One-pot template synthesis and crystal structure of two new polyaza copper(II) complexes

A new 14-membered hexazamacrocyclic copper(II) complex [Cu(H₂L¹)](ClO₄)₄(L¹=1,8-bis(2-aminoethyl)-1,3,6,8,10,13-hexaazacyclotetradecane) has been prepared by the one-pot reaction of ethylenediamine and formaldehyde in the presence of the Cu(II) ion. The crystal structure of [Cu(H₂L¹)](ClO₄)₄ was determined by X-ray diffraction. It crystallizes in the triclinic space group P−1 with a=12.118(2) Å, b=12.438(2) Å, c=12.466(2) Å, α=102.26(1)°, β=112.82(1)°, γ=111.51(1)°, and Z=2. The coordination geometry around the copper(II) ions is axially elongated octahedral with four nitrogen atoms of the macrocycle [Cu–N 2.012(7) Å for Cu(1) and 2.013(6) Å for Cu(2), average value] and two oxygen atoms of two ClO₄⁻ anions [Cu–O=2.550 Å for Cu(1) and 2.601(6) Å for Cu(2)]. [CuL²](ClO₄)₂(L²=3,7-bis(2-aminoethyl)-1,3,5,7-tetraazabicyclo[3,3,2]decane) with a novel tetraazabicyclic ligand was obtained from the same reaction system as an additional product. Crystal structure of [CuL²](ClO₄)₂: monoclinic space group Cc, a=16.393(3) Å, b=8.8640(18) Å, c= 13.085(3) Å, β=105.01(3)°, and Z=4.     

The first example of half-sandwich cobalt(III) complex with hydrotris(pyrazolyl)borate ligand

This paper presents the synthesis, crystal structure and spectroscopic properties of a novel half-sandwich mononuclear cobalt(III) complex with hydrotris(3,5-dimethylpyrazolyl)borate ligand and thiocyanate [Tp^*Co(Hpz^*)(NCS)₂]·H₂O·CH₃OH (Tp^*: hydrotris(3,5-dimethyl- pyrazolyl)borate, Hpz^*: 3,5-dimethylpyrazole). The structure was determined by X-ray diffraction. The complex crystallizes in the monoclinic system, space group C_c, a=18.591(6) Å, b=10.536(3) Å, c=17.568(5) Å, β=11.284(5)°, Z=4, R₁=0.0501, wR₂=0.1179. The cobalt(III) ion in the complex is six-coordinated with nitrogen atoms, three from Tp^*, two from pyrazole and two from two thiocyanates, to form octahedral environment. The hydrogen atoms of O(2) of water molecule are connected by hydrogen bonds with S atoms of two adjacent complex molecules to form 1-D chains. The hydrogen atom of N(8) of complex molecule is connected by hydrogen bond with methanol. The spectroscopic results are consistent with the crystallographic study.     

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.     

A novel double-helical-chain coordination polymer constructed from 2,2′-biphenyldicarboxylate-linked binuclear-copper motif

The first 1-D double-helical-chain coordination polymer, [(H₂O)Cu(BPDC)] (2,2^′-biphenyldicarboxylate), based upon the binuclear square pyramidal copper(II)-pair motifs has been synthesized under hydrothermal conditions and characterized by single crystal X-ray diffraction technique. [(H₂O)Cu(BPDC)] crystallized in orthorhombic crystal system, space group Cmca with unit cell dimensions a=21.073(6) Å, b=7.118(2) Å and c=17.670(5) Å, Z=8.     

Synthesis and characterization of the firstly observed two brilliantly triboluminescent lanthanide complexes: 2-hydroxyethylammonium and pyrrolidinium tetrakis(dibenzoylmethide) europate(III). Crystal structure of one brilliantly triboluminescent acentric complex: dimethylbenzylammonium tetrakis(dibenzoylmethide)europate

Triboluminescent phenomena of 2-hydroxyethylammonium tetrakis (dibenzoylmethide)europate (1) and pyrrolidonium tetrakis(dibenzoylmethide)europate (2) were firstly observed, and the crystal structure of dimethylbenzylammonium tetrakis(dibenzoylmethide)europate (3) was successfully determined after more than 35 years later. Crystal data for 3: orthorhombic, space group Pca2₁ (No.29), a=25.697(2), b=9.462(3), c=15.023(3) Å, Z=4. The Eu atom exhibits an eight-coordinate tetragonal antiprismatic geometry with an average Eu–O bond distance of 2.42(2) Å. Triboluminescent spectra of 1–3 are basically similar to that of their fluorescent spectra, and the observed triboluminescent emission correlates well with their acentric space group.     

Eu5(μ4-OH)(μ3-OH)4(μ-DBM)4(DBM)6 (DBM=dibenzoylmethide): a novel Eu5 square-pyramid polynuclear complex with a rare μ4-OH bridging mode

The reaction of EuOCl (EuCl₃) with dibenzoylmethane (HDBM) in the presence of N-methylmorpholine yields a novel Eu₅ square-pyramid polynuclear complex with a rare μ₄-OH bridging mode, Eu₅(μ₄-OH)(μ₃-OH)₄(μ-DBM)₄(DBM)₆ (1). The compound was characterized by elemental analysis, IR, fluorescence and Mössbauer spectra as well as by an X-ray single crystal structure determination. Crystallographic data for 1, C₁₅₀H₁₁₅Eu₅O₂₅, monoclinic, P2₁/c, a=22.223(5), b=17.427(1), c=35.708(5) Å, β=100.11(2)°, V=13614(4) ų, Z=4, R₁=0.0979, wR₂=0.1695.     

Crystal and geometry-optimized structure,Hirshfeld surface analysis and spectroscopic studies of tetrachlorocuprate and nitrate salts of 1-(2-fluorophenyl)piperazine cations, (C10H15FN2)[CuCl4] (I) and (C10H14FN2)[NO3] (II)

Two new organic-inorganic hybrid materials, 1-(2-fluorophenyl)piperazine-1,4-diium tetrachlorocuprate, (C₁₀H₁₅FN₂)[CuCl₄] (I) and 1-(2-fluorophenyl)piperazin-4-ium nitrate, (C₁₀H₁₄FN₂)[NO₃] (II), have been synthesized by an acid/base reaction at room temperature in the presence of 1-(2-fluorophenyl)piperazine as an organic-structure directing agent and their structures were determined by single crystal X-ray diffraction. Compound (I), (C₁₀H₁₅FN₂)[CuCl₄], crystallizes in the monoclinic system and P2₁/c space group with a = 7.5253 (2), b = 20.6070 (7), c = 9.7281 (3) Å, β = 103.6730 (17)°, V = 1465.82 (8) Å³ with Z = 4. Full-matrix least-squares refinement converged at R = 0.037 and wR(F²) = 0.088. Compound (II), (C₁₀H₁₄FN₂)[NO₃], belongs to the monoclinic system, space group P2₁/c with the following parameters: a = 10.8034 (2), b = 7.5775 (1), c = 14.4670 (3) Å, β = 111.761 (2)°, V = 1099.91 (4) ų and Z = 4. The structure was refined to R = 0.044, wR(F²) = 0.136.In the structures of (I) and (II), the anionic and cationic entities are interconnected by means of set of hydrogen bonding contacts forming three-dimensional networks. Intermolecular interactions were investigated by Hirshfeld surfaces and the contacts of the four different chloride atoms were notably compared. The results of the optimized molecular structure are presented and compared with the experimental one. The Molecular Electrostatic Potential (MEP) maps and the HOMO and LUMO energy gap of both compounds were computed. The vibrational absorption bands were identified by infrared spectroscopy. Theory (DFT) calculations of normal mode frequencies are compared with experimental ones.     

Metal–Organic Framework Based on Pyridine-2,3-Dicarboxylate and a Flexible Bis-imidazole Ligand: Synthesis, Structure, and Photoluminescence

A novel metal–organic framework {[Zn(2,3-pydc)(bbi)]·0.5CH₃CN·2H₂O} _n (2,3-pydc = pyridine-2,3-dicarboxylate, bbi = 1,1′-(1,4-butanediyl)bis(imidazole)) (1), was prepared under hydrothermal conditions and characterized by elemental analyses, IR and X-ray diffraction. Crystal data for 1 are monoclinic, space group C2/c, a = 19.685(2) Å, b = 14.332(1) Å, c = 16.930(2) Å, β = 121.205(2)°, U = 4085.3(6) Å³, Z = 4. The results reveal that the Zn(II)-atom is five-coordinated with two O-atoms and three N-atoms forming a distorted trigonal bipyramidal geometry. The Zn(II) atoms are bridged by 2,3-pydc and bbi ligands, leading to a three-dimensional network. The Zn···Zn separations are 8.277 Å [through the 2,3-pydc bridge] and 12.638 Å [through the bbi bridge]. Additionally, 1 shows strong fluorescence in the solid state at room temperature.     

Synthesis and characterization of the zinc(II) complex of a bleomycin analogue: a unique polymeric 2-[((2-(4-imidazoyl)ethyl)amino)carbony]-6-[((2-amino-2-methylpropyl)amino)methyl]pyridine zinc(II) nitrate complex

The reaction of 2-[((2-(4-imidazoyl)ethyl)amino)carbonyl]-6-[((2-amino-2-methylpropyl)amino)methyl]pyridine (L) with Zn^II(NO₃)₂·6H₂O has afforded a novel one-dimensional polymeric Zn^II complex, (Zn^II(L)(NO₃)₂)_n (2). Complex 2 crystallizes in the space group P2₁/n with a=8.955(3), b=13.216(3), c=18.941(3) Å, β=103.39(2)°, V=2180.6(10) ų, and Z=4. The geometry of each Zn^II is approximately a trigonal bipyramid: three nitrogens and one oxygen of the amide group are coordinated to the zinc while the fifth site is occupied by the imidazole nitrogen of a neighboring unit.     

Synthesis,reactivity, and X-ray structural characterization of a vanadium(III) oxidation pre-catalyst, (CpPOEtCo)VCl2(DMF)

Vanadium complexes are extensively used in the chemical industry as oxidation catalysts. During the course of our investigations into vanadium oxidation catalysis, the rich reactivity of a vanadium(III) scorpionate analogue complex, (CpP^OEtCo)VCl₂(DMF) (1), was investigated. The octahedrally coordinated 1 was prepared by mixing vanadium(III) chloride with Na(CpP^OEtCo) in DMF. The crystal structure of 1 has been determined through X-ray diffraction. Complex 1, C₂₀H₄₂Cl₂CoNO₁₀P₃V, crystallizes in the monoclinic space group P2₁/c with a = 38.566(9) Å, b = 9.499(2) Å, c = 18.149(4) Å, and β = 100.485(4)° with Z = 8. Complex 1 was found to be an effective pre-catalyst for the oxidation of 3,5-di-tert-butylcatechol to 3,5-di-tert-butylquinone. The reactivity studies, oxidative catalytic ability, as well as X-ray structural characterization of (CpP^OEtCo)VCl₂(DMF) will be discussed. ((CpP^OEtCo) = [η⁵-cyclopentadienyltris(diethylphosphito-κ¹P) cobaltate(III)⁻; DMF = N,N-dimethylformamide).     

A dinuclear zinc(II) complex of 2,6-bis[((2-hydroxybenzyl)(2-pyridylmethyl)amino)methyl]-4-methylphenol derived from bis(acetylacetonato)zinc(II)

Reaction of the symmetrical proligand H₃L with bis(acetylacetonato)zinc(II) has given the homodinuclear complex [Zn₂L(acac)]·CH₃CN in which one of the pendant phenolato groups functions as a bridge for the dinuclear zinc centre. The complex crystallises in the triclinic space group P-1, with unit cell parameters a=10.0250(11) Å, b=10.6132(13) Å, c=19.139(2) Å, α=80.418(2)°, β=75.792(2)°, γ=84.532(2)°.     

Hydrothermal synthesis and crystal structure of a new copper(II) molybdenum(VI) arsenate(III), (C5H5NH)2(H3O)2[(CuO6)Mo6O18(As3O3)2]

A new copper(II) molybdenum(VI) arsenate(III), (C₅H₅NH)₂(H₃O)₂[(CuO₆)Mo₆O₁₈(As₃O₃)₂], has been hydrothermally synthesized and characterized by single crystal X-ray diffraction and TG analysis. The compound crystallizes in the monoclinic space group P2₁/n with a=9.303(2), b=20.731(4), c=12.617(3) Å, β=104.17(3)°, V=2359.3(8) ų, Z=2 and R1(wR2)=0.0296(0.0683). The structure is composed of pyridinium cations, proton hydrates and [(CuO₆)Mo₆O₁₈(As₃O₃)₂]⁴⁻ polyanions. The polyanion framework derives from the Anderson type; the central octahedron is filled up by copper(II) and is capped on both sides by a cyclic As₃O₆ group.     

Synthesis of 1,1′-ferrocene bis(carboxypyrazole) compounds and displacement of the pyrazole ligands

The reaction of 1,1′-ferrocenedicarbonyl chloride with pyrazole or 3,5-dimethyl pyrazole generates novel 1,1′-ferrocene bis(amide) compounds 1 and 2, respectively. The crystal structure of 1 shows that the pyrazole rings are essentially co-planar with each other and with the cyclopentadienyl rings. Attempts to use the complexes as a chelating ligand were unsuccessful. Instead, treatment of 1 or 2 with Mo(CO)₄(pip)₂, pip = piperidine, led to displacement of the pyrazole ligands and formation of the known amide compound, 1,1′-ferrocene bis carbonyl piperidine. Replacement of the pyrazole is ascribed to the weakness of the amide bond caused by the aromaticity of the pyrazole ring. Crystal data for C₁₈H₁₄FeN₄O₂ (1): monoclinic P2(1)/c, a = 13.3907(18) Å, b = 10.2112(14) Å, c = 11.3082(16) Å, β = 105.209(2)°, V = 1492.1(4) Å³, Z = 4.     

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.     

Cage-opening supramolecular isomerism in Cu(II) complexes

Reactions of Cu(NO₃)₂·3H₂O or Cu(CF₃SO₃)₂·6H₂O with semirigid ligands 2,6-bis(pyridin-3-ylmethyl)-3a,4,4a,7a,8,8a-hexahydro-4,8-ethenopyrrolo[3,4-f]isoindole-1,3,5,7(2H,6H)-tetraone (L1) and 2,6-bis(pyridin-4-ylmethyl)-3a,4,4a,7a,8,8a-hexahydro-4,8-ethenopyrrolo[3,4-f]isoindole-1,3,5,7(2H,6H)-tetraone (L2) result in 0D tetragonal prismatic cage (1, 4), 1D loop-and-chain (2, 5, 6), and 2D (4,4) network (3) metal-organic complexes, which comprise of U_a, U_b or Z type ligand conformations, respectively. Solid state X-ray diffraction and solution state ESI-MS analyses manifest the ring-opening isomerization mechanism among the complexes, and photoluminescence properties are also studied.