Synthesis and crystal structure of the complex [Mg(H2O)2(dmf@CB[6])(bdc)]·DMF·4H2O and the inclusion compound [dmf@CB[6]]·8H2O

The complex [Mg(H₂O)₂(dmf@CB[6])(bdc)]·DMF·4H₂O (1) and the inclusion compound [dmf@CB[6]]·8H₂O (2) were obtained from a mixture of magnesium perchlorate and water (for compound 1) or magnesium oxide and H₂SO₄ (for compound 2), and cucurbit[6]uryl (CB[6]) in the presence of N,N-dimethylformamide (DMF) with the additives of terephthalic or fumaric acid, respectively. X-ray diffraction studies showed that magnesium cation in compound 1 coordinated two oxygen atoms of the CB[6] molecule, one oxygen atom of the terephthalate anion, two molecules of water, and a DMF molecule located inside the cucurbit[6]uryl cavity. When fumaric acid was used instead of terephthalic acid under similar conditions of synthesis, no coordination of magnesium cations to cucurbit[6]uryl molecules took place, rather an inclusion compound of DMF into the macrocyclic cavitand was formed. Compounds 1 and 2 were characterized by X-ray diffraction data, IR spectroscopy, and elemental analysis.     

Synthesis, crystal structure and electrochemical properties of [Co(phen)3] · (H3btec) · (H2btec)0.5 · DMF · 6H2O

A new complex [Co(phen)₃] · (H₃btec) · (H₂btec)_0.5 · DMF · 6H₂O (1) (H₄btec = 1,2,4,5-Benzenetetracarboxylic acid, phen = 1,10-phenanthroline, DMF = dimethylformamide) was synthesized by the reaction of pyromellitic dianhydride, phen · H₂O and CoSO₄ · 7H₂O. Complex 1 crystallizes in the triclinic system, space group P-1 with a = 11.8123(14) ?, b = 13.0356(16) ?, c = 17.575(2) ?, ?? = 91.461(2)°, ?? = 101.347(2)°, ?? = 99.830(2)°, FW = 1159.94, Z = 2, V = 2609.5(5) ?³. X-ray crystal structural determination indicates that the Co(II) ion is octahedral coordinated by six nitrogen atoms of three phenanthroline ligands. The [Co(phen)₃]²⁺ cation engages its phen ligands in ??-?? interactions with H₂btec anion. Extensive hydrogen bonding interactions occur between water molecules, DMF, H₃btec and H₂btec anions. The highly-crystalline compounds 1, which are insoluble in water as well as common organic solvents, have been characterized in the solid-state by elemental analysis, thermogravimetric analysis and IR spectra. Moreover, the study of the electrochemistry of complex 1 was carried out by using cyclic voltammetry. It revealed that the Co(II) complex exhibits a quasi-reversible one-electron redox process.     

Synthesis and crystal structures of supramolecular compounds: [Cu(mpca)2(H2O)] · 3H2O and [Cu2(mpca)2(pyr)4]

A new chelate ligand, 5-methyl-1H-pyrazole-3-carboxylic acid (mpca), has been synthesized. This ligand reacts with cupric sulfate to give two supramolecular compounds [Cu(mpca)₂(H₂O)] · 3H₂O (1) and [Cu₂(mpca)₂(pyr)₄] (Pyr = pyridine) (2), which were characterized by elemental analysis and X-ray crystal diffraction. Helical water chain and strong π–π interaction are important for the stability of the 3-D structure of these supramolecules.     

Synthesis and properties of Na6[Pb(S2O3)4] · 6H2O

Conditions for the synthesis of the water-soluble lead thiosulfate complex Na₆[Pb(S₂O₃)₄] · 6H₂O were determined. The complex synthesized was characterized by UV and IR spectroscopy and X-ray phase and thermal analyses. Thermolysis schemes were proposed on the basis of the IR and mass spectra of the thermal decomposition products.     

Synthesis, crystal structure, and thermal analysis of hexahydrogen dodecavanadate of composition [NH3 · H2O]6 · H6[Ca4V12O40] · 6H2O

Dihydrogen dodecavanadate of composition [NH₃ · H₂O]₆ · H₆[Ca₄V₁₂O₄₀] · 6H₂O was synthe-sized and studied by X-ray crystallography and TGA analyses. The crystals are cubic, space group I $\bar 4$ 3m;; unit cell parameters: a = 13.518(2) ?, V = 2470.4(3) ?³, ??_calc = 2.2334 g/cm³, Z = 2.     

Structure and properties of tripyridine nitrosocomplexes of ruthenium: mer-[Ru(NO)Py3Cl(OH)]Cl·1.5H2O and mer-[Ru(NO)Py3Cl(H2O)]Cl2·2H2O·0.5HCl

The reaction of K₂[Ru(NO)Cl₅] with pyridine in aqueous ethanol at pH ～ 7–8 affords a nitrosoruthenium hydroxocomplex mer-[Ru(NO)Py₃Cl(OH)]Cl·1.5H₂O (I) (yield ～55%). Treatment of hydroxocomplex I with hydrochloric acid at room temperature gives the aqua complex mer-[Ru(NO)Py₃Cl(H₂O)]Cl₂·2H₂O·0.5HCl (II). The structures of the compounds are determined by X-ray crystallography: I, space group P2₁/n, a = 9.2292(4) Å, b = 11.7781(4) Å, c = 17.4915(7) Å, β = 90.9560(10)°, R = 4.84%; II, space group P-1, a = 7.3528(9) Å, b = 11.5793(11) Å, c = 13.6961(16) Å, α = 84.558(3)°, β = 87.668(4)°, γ = 74.146(4)°, R = 6.22%. Compounds I and II are characterized by powder XRD, ¹H and ¹³C NMR, and IR spectroscopy. The thermal decomposition of compound II in the inert atmosphere is examined by thermal analysis.     

Syntheses,crystal structures and magnetic properties of two honeycomb-layered bimetallic assemblies,K2[NiII(cyclam)]3[FeII(CN)6]2 · 12H2O and [NiII(cyclam)]3[FeIII(CN)6]2 · 16H2O

Two bimetallic assemblies, K₂[Ni^II(cyclam)]₃[Fe^II(CN)₆]₂ · 12H₂O (1) and [Ni^II(cyclam)]₃[Fe^III(CN)₆]₂ · 16H₂O (2) (cyclam = 1,4,8,11-tetraazacyclotetradecane), were obtained by reaction of K₄[Fe(CN)₆] and [Ni(cyclam)](ClO₄)₂ in aqueous media at different temperatures. Their crystals were structurally determined and magnetic properties were studied. Both of the compounds have honeycomb-layered structures, which are formed by Fe₆Ni₆ units linked through the cyanide bridges. Structure (1) consists of polyanions containing Ni^II–NC–Fe^II linkages and K⁺ cations, while structure (2) is a two-dimensional neutral layer containing Ni^II–NC–Fe^III linkages. The magnetic properties of (1) and (2) have been investigated in the 5–300 K range. Compound (1) exhibits a weak antiferromagnetic interaction with Weiss constant = –0.35 K; compound (2) shows ferromagnetic intralayer and antiferromagnetic interlayer interactions.     

(NH4)(CN3H6)2[UO2(C2O4)2(NCS)] · 2H2O: Synthesis and crystal structure

A single-crystal X-ray diffraction study (NH₄)(CN₃H₆)₂[(UO₂(C₂O₄)₂(NCS)] · 2H₂O (I) was carried out. The crystals are orthorhombic, space group P2₁2₁2₁, Z = 4, with the unit cell parameters a = 6.668(2) Å, b = 13.463(4) Å, c = 23.086(6) Å. The main structural units of the crystals of I are insular complex anions [(UO₂)(C₂O₄)₂(NCS)]^3?. They belong to the crystal-chemical group AB ₂ ⁰¹ M¹ (A = UO ₂ ²⁺ ) of uranyl complexes and are linked into a three-dimensional framework through electrostatic interactions and hydrogen bonds with the participation of ammonium and guanidinium cations and crystal water molecules.     

[Ru(NH3)6](MoO4)Cl·3H2O and [M(NH3)6](ReO4)3·2H2O (M = Ru, Ir). Synthesis and crystal structure

X-ray crystallographic analysis is used to determine the crystal structures of [Ru(NH₃)₆](MoO₄)Cl·3H₂O and [M(NH₃)₆](ReO₄)₃·2H₂O (M = Ru, Ir) complex salts. The features of the fragment packing are studied.     

Synthesis and Crystal Structure of [Ni(H2O)6][Ni(H2O)2(C4H2O4)]·4H2O

Reaction of a freshly prepared Ni(OH)_{2?2 x} (CO₃) _x ·yH₂O with maleic acid in H₂O at room temperature afforded [Ni(H₂O)₆][Ni(H₂O)₂(C₄H₂O₄)]·4H₂O, which consists of [Ni(H₂O)₆]²⁺ cations, [Ni(H₂O)₂(C₄H₂O₄)]^2? anions and lattice H₂O molecules. Ni atoms in cations are octahedrally coordinated and Ni atoms in anions are each octahedrally coordinated by bidentate chelating maleato ligands and two water molecules at trans positions. Cations and anions are interlinked by hydrogen bonds to form 1D chains, which are hexagonally arranged and connected by the lattice water molecules. When heated in a flowing argon stream, the compound decomposes, with complete dehydration being followed by dissociation of nickel maleate into NiO and maleic anhydride.     

Synthesis, crystal structure, and thermal stability of [Mo2O4(μ2-O)(C6H4O2)2(H2O)] · (C8H9N2)2 · 2H2O

From hydrothermal treatment of benzene-1,2-diamine, pyrocatechol, and MoO₃ in acetic acid solution, a new compound, [Mo₂(μ₂-O)₂(C₆H₄O₂)₂(H₂O)] · (C₈H₉N₂)₂ · 2H₂O (I), constructed from pyrocatechol chelated dinuclear molybdenum units and 2-methylbenzimidazole has been synthesized. Single-crystal structure analysis reveals that the compound crystallizes in the monoclinic space group P2₁/c with a = 23.365(2), b = 7.2214(5), c = 19.3021(16) β = 97.929(4), V = 3225.6(5), Z = 4, M = 808.46, ρ_c = 1.665 g/cm³, μ(MoK _α) = 0.84 mm^?1, F(000) = 1608, the final R = 0.0622 and wR = 0.1484 for 7385 independent reflections with R _int = 0.0393. Interestingly, an in situ condensation between acetic acid and benzene-1,2-diamine has occurred, and the unexpected 2-methyl-1-H-benzo[d] imidazoles serve as counterions and N-H donors to form stable hydrogen-bond network in the crystal. Furthermore, intermolecular hydrogen bonds are found among the cations, anions and crystalline water molecules. The double nuclear molybdenum units are connected by O-H...O hydrogen bonds with the crystalline water molecules to form one-dimensional chains, and the chains are further joined together by N-H...O to form a quasi-two dimensional structure.     

Synthesis and crystal structure of [La(NO3)3(H2O)2(BiPy)]·1.5(BiPy)

The molecular and crystal structure of the [La(NO₃)₃(H₂O)₂(2.2′-BiPy)]·1.5(2.2′-BiPy) compound is determined. The metal coordination polyhedron in the La(III) complex is formed from 10 donor atoms of O₈N₂: 6 oxygen atoms belong to three chelate-coordinated NO ₃ ^? anions, 2 oxygen atoms belong to two water molecules, and 2 nitrogen atoms belong to a bidentate bipyridine molecule coordinated in the neutral form. The structure is based on the metal complexes linked together in chains through the O(W)-H...O hydrogen bonds, in which oxygen atoms of the coordinated NO ₃ ^? anions act as acceptors. It is a framework structure, further stabilized by a system of O(W)-H...N and C-H...N hydrogen bonds, in which nitrogen atoms of the uncoordinated bipyridine molecules act as proton acceptors.     

Synthesis, crystal structure, and photophysical properties of acid (H3O)2[{W6Br8}Br6] · 4H2O

Compound (H₃O)₂[{W₆Br₈}Br₆] · 4H₂O is synthesized by the reaction of polymeric tungsten bromide W₆Br₁₂ with hydrobromic acid in an ethanolic solution. The structure of the compound is a packing of counterions H₃O⁺ and [{W₆Br₈}Br₆]^2? and crystallization water molecules joined with each other by an extended system of hydrogen bonds. The finely crystalline sample of the complex exhibits luminescence, whose spectrum has a broad profile from ??500 nm to more than 950 nm with a maximum at ??715 nm, with an absolute quantum yield of ??0.225. The emission is characterized by the biexponential decay with lifetimes of ??2.2 and ??8.4 ??s.     

Ammonium and potassium citratogermanates(IV): Synthesis, chemical compositions, and structures. The crystal structures of (NH4)[Ge(OH)(H2Cit)2] · H2O and K4[Ge(HCit)2(H2Cit)] · 3H2O

Methods for the synthesis of ammonium citratogermanate (NH₄)[Ge(OH)(H₂Cit)₂] · H₂O (I) and potassium citratogermanate (K₄[Ge(HCit)₂(H₂Cit)] · 3H₂O (II), where H₄Cit is citric acid) in aqueous MeCN were developed. The individuality, chemical composition, and thermal stability of complexes I and II were proved by elemental analysis, thermogravimetry, and IR spectroscopy. According to X-ray diffraction data, the coordination numbers of the Ge atoms are 5 and 6 and their coordination polyhedra are a square pyramid and an octahedron in complexes I and II, respectively. In both complexes, the Ge atom coordinates the deprotonated OH group and the α-carboxyl group of the ligands H _n Cit^4?n to form five-membered chelate rings. Hydrogen bonds in I as well as potassium cations in II serve to unite these complexes into frameworks.     

Synthesis and crystal structure of (H3O)2{(Na2(OH)CB[5])2[HV4O12]}Cl · 14H2O

The compound (H₃O)₂{(Na₂(OH)CB[5])₂[HV₄O₁₂]}Cl · 14H₂O is synthesized by heating (120°C) of a mixture of sodium vanadate, cucurbit[5]uril (CB[5]), rubidium chloride, and water in a sealed ampule. According to the X-ray diffraction data, the binding of the [Na₂(OH)]⁺ binuclear cation with CB[5] occurs due to the bidentate coordination of the oxygen atoms of the portals of cucurbit[5]uril to the sodium atoms. The tetranuclear vanadium complex [HV₄O₁₂]^3? serves as a bridge, joining infinite chains {Na₂(OH)CB[5]} _∞ ⁺ in pairs.     

Synthesis and crystal structure of KBi(C6H4O7) · 3.5H2O

A novel compound, KBi(C₆H₄O₇) · 3.5H₂O (I), has been synthesized in the Bi(NO₃)₂-K₃(HCit) system (HCit^3? is an anion of citric acid C₆H₈O₇) at a component ratio (n) of 8 in a water-glycerol mixture, and its crystal structure has been determined. The crystals are unstable in air. The crystals are triclinic: a = 7.462 Å, b = 10.064 Å, c = 17.582 Å, α = 100.27°, β = 99.31°, γ = 105.48°, V = 1221.2 ų, Z = 2, space group $P\bar 1$ . In the structure of I, asymmetric binuclear fragments [Bi₂(Cit^4?)₂(H₂O)₂]^2? are linked through inversion centers into polymeric chain anions. Ions K⁺ and crystal water molecules are arranged in channels between the chains. The Bi(1)...Bi(2) distances in the binuclear fragment are 4.62 Å, and the Bi(1)...Bi(1) and Bi(2)...Bi(2) distances between bismuth atoms in the chain are 5.83 and 5.95 Å, respectively. The chains are linked through bridging oxygen atoms of the ligands Cit to form layers. In the centrosymmetric four-membered chelate ring Bi₂O₂ formed through Bi-O(Cit) bonds, the distances Bi(1)-Bi(1) are equal to 4.55 Å, and Bi(1)-O are 2.66 and 2.84 Å. The Bi-O bond lengths in I are in the range 2.12–3.16 Å. The Cit ligands act as hexadentate chelating/bridging ligands.     

Synthesis, crystal structure, and fluorescence properties of a novel coordination polymer [Zn(L)(4,4′-bipyridine)(H2O)] n · (H2O)4

In this work, a novel and rare coordination polymer, [Zn(L)(Bipy)(H₂O)] _n · (H₂O)₄ (H₂L??sphenylpropylmalonate acid, Bipy??4,4??-bipyridine), has been synthesized and characterized by elemental analysis, FT-IR spectroscopy, and solid fluorimetry studies. In the crystal, the Zn²⁺ ion of the complex is hexacoordinated in a slightly distorted octahedral configuration forming the unit structure, 2D structure, and 3D framework. The supramolecular architecture was constructed by a unit of (H₂O)₄ discrete water cluster. Besides, the coordination polymer displays strong emission spectra due to the metal-to-ligand charge-transfer transition, having potential applications as fluorescent materials.