Проектна діяльність бібліотек та інформаційних установ

Робоча навчальна програма «Проектна діяльність бібліотек та інформаційних установ» за напрямом підготовки 6.020102 «Книгознавство, бібліотекознавство і бібліографія», галузі знань 0201 «Культура», освітній рівень: перший (бакалаврський). - 2017 р

Fast Preparation of Dimorphic Thioantimonates and a Thioantimonate with a Hitherto Unknown Network Topology Applying a New Synthesis Approach

The reaction of an aqueous solution of Na₃SbS₃ with [Ni­(terpy)₂]²⁺ (terpy = 2,2′:6′,2″-terpyridine) afforded crystallization of three new thioantimonates in short reaction times. Two polymorphic compounds, [Ni­(terpy)₂]­[Sb₄S₇]­·H₂O (<b>1</b>, <b>2</b>), were obtained simultaneously under identical reaction conditions, while an increase of the reaction temperature led to formation of the third compound [Ni­(terpy)₂]₂­[Sb₁₀S₁₇] (<b>3</b>). In <b>1</b> the anion consists of a [Sb₄S₇]^2– chain, whereas <b>2</b> is composed of a layered [Sb₄S₇]^2– anion. Form <b>2</b> disappeared at longer reaction times, and therefore modification <b>1</b> might represent the thermodynamically stable form at this temperature despite the lower density compared to <b>2</b>. Storing modification <b>1</b> at elevated temperatures the water can partly be removed in a topotactic reaction leading to the compound [Ni­(terpy)₂]­[Sb₄S₇]­·0.25 H₂O (<b>1A</b>). Compound <b>3</b> exhibits a unique Sb:S ratio, and a never before observed network topology significantly enhancing the structural diversity of thioantimonates­(III)

Influence of the Synthesis Parameters onto Nucleation and Crystallization of Five New Tin–Sulfur Containing Compounds

The distinct control of the synthesis parameters achieved crystallization of five new inorganic–organic hybrid tin sulfides with 1,10-phenanthroline (phen) as the organic component: {[Mn­(phen)₂]₂(μ₂-Sn₂S₆)} (<b>1</b>, <b>3</b>), {[Mn­(phen)₂]₂(μ₂-Sn₂S₆)}·phen (<b>2</b>), {[Mn­(phen)₂]₂(μ₂-Sn₂S₆)}·phen·H₂O (<b>4</b>), and {[Mn­(phen)₂]₂[μ-η²-η²-SnS₄]₂[Mn­(phen)]₂}·H₂O (<b>5</b>). Compounds <b>1</b>, <b>3</b>, and <b>4</b> occur successively under static conditions by increasing the reaction time up to 8 weeks. Stirring the reaction mixtures and keeping the educt ratio constant allow preparation of distinct phase pure samples within very short reaction times. At higher autogenous pressure, crystallization and conversion of several compounds are suppressed, and only <b>1</b> crystallized. Compound <b>2</b> could only be obtained in glass tubes at low pH value of the reaction mixture or at low amine concentration. Adjusting the pH value of the solution, the concentration, and the volume of the solvent, compounds <b>1</b>–<b>4</b> crystallize sequentially and were successively converted into each other. Results of thermal stability experiments and solubility studies suggest that compounds <b>1</b> and <b>3</b> are polymorphs following the density rule. Compounds <b>2</b> and <b>4</b> may be viewed as pseudopolymorphs of <b>1</b> and <b>3</b>

Applying Ni(II) Amine Complexes and Sodium Thiostannate as Educts for the Generation of Thiostannates at Room Temperature

A new versatile and fast room temperature synthesis route was developed in which Na₄SnS₄·14H₂O and selected Ni­(II)­amine complexes (amine = ethylenediamine (en), 1,2-diaminocyclohexane (1,2-dach), 1,2-diaminopropane (1,2-dap), 2-(aminomethyl)­pyridine (2amp)) were reacted in aqueous tren (tren = tris­(2-aminoethyl)­amine) solutions affording crystallization of six new compounds. During the reaction heteroleptic Ni²⁺ centered complexes are formed in situ by replacement of two bidentate ligands by the tetradentate tren molecule. The compounds poorer in water of the pseudopolymorphs of [Ni­(tren)­(en)]₂­[Sn₂S₆]­·<i>x</i>H₂O (<i>x</i> = 2 (<b>1</b>) and 6 (<b>2</b>)) and [Ni­(tren)­(1,2-dach)]₂­[Sn₂S₆]­·<i>x</i>H₂O (<i>x</i> = 3 (<b>3</b>) and 4 (<b>4</b>)) are formed after a very short reaction time of 1 day. Remarkably, keeping the reaction slurries at room temperature for 7 days the thermodynamically stable water richer compounds were obtained. The remaining compounds, [Ni­(tren)­(1,2-dap)]₂­[Sn₂S₆]­·4H₂O (<b>5</b>) and [Ni­(tren)­(2amp)]₂­[Sn₂S₆]­·10H₂O (<b>6</b>), crystallized between 1 and 7 days. The water of crystallization molecules in all compounds are involved in extended hydrogen bonding interactions significantly affecting the packing of cations and anions. Hirshfeld surfaces analyses give a detailed picture of intermolecular interactions which lead to the different packing motifs in the crystal structures

Metamagnetism and Slow Relaxation of the Magnetization in the 2D Coordination Polymer: [Co(NCSe)₂(1,2-bis(4-pyridyl)ethylene)]_<i>n</i>

Reaction of Co­(NCSe)₂ with 1,2-bis­(4-pyridyl)­ethylene (bpe) leads to the formation of [Co­(NCSe)₂(1,2-bis­(4-pyridyl)­ethylene)]_<i>n</i>, in which Co­(NCSe)₂ chains are linked by the bpe ligands into a two-dimensional (2D) coordination network. This compound shows metamagnetic behavior with slow relaxation of the magnetization above the critical field (<i>H</i>_C) and dominating antiferromagnetic exchange below <i>H</i>_C. This is a very rare phenomenon which was never observed before in a 2D selenocyanato coordination polymer

Molybdenum 17- and 18-Electron Bis- and Tris(Butadiene) Complexes: Electronic Structures, Spectroscopic Properties, and Oxidative Ligand Substitution Reactions

New results on the electronic structures, spectroscopic properties, and reactivities of the molybdenum tris­(butadiene) and tris­(2,3-dimethylbutadiene) complexes [Mo­(bd)₃] (<b>1</b>^<b>bd</b>) and [Mo­(dmbd)₃] (<b>1</b>^<b>dmbd</b>), respectively, are reported. Importantly, the metal ligand bonding interaction can be weakened by oxidizing the metal center with ferrocenium salts. The addition of the bidentate phosphine ligand 1,2-bis­(diphenylphosphino)­ethane then leads to a new type of stable 17-electron complex, [Mo­(dmbd)₂(dppe)]­(X) (<b>2</b>; X = BF₄^–, PF₆^–, BPh₄^–), where one of the butadiene ligands is exchanged by a chelating phosphine. Reduction of the cationic complexes <b>2</b> generates the corresponding 18-electron complex [Mo­(dmbd)₂(dppe)] (<b>3</b>), thus establishing a new strategy for ligand substitution reactions in [Mo­(bd)₃] complexes via one-electron oxidized intermediates. The new heteroleptic molybdenum complexes are characterized by X-ray structure analysis; vibrational, NMR, and EPR spectroscopy; and electrochemistry. DFT calculations are performed to explain the structural and specroscopic trends observed experimentally. For compound <b>1</b>^<b>bd</b>, a normal coordinate analysis is presented, providing additional information on the bonding situation in this type of complex

Bonding and Activation of N₂ in Mo(0) Complexes Supported by Hybrid Tripod Ligands with Mixed Dialkylphosphine/Diarylphosphine Donor Groups: Interplay of Steric and Electronic Factors

Molybdenum dinitrogen complexes are presented which are supported by novel hybrid tripod ligands of the type Me-C­(CH₂PPh₂)₂(CH₂PⁱPr₂) (<b>trpd-1</b>) and H–C­(CH₂PPh₂)­(CH₂PⁱPr₂)₂ (<b>trpd-2</b>) having mixed dialkylphosphine/diarylphosphine donor groups. Reaction of the ligand <b>trpd-1</b> with [MoI₃(thf)₃] followed by sodium amalgam reduction in the presence of the dppm gives the dinitrogen complex [Mo­(N₂)­(trpd-1)­(dmpm)] where <b>trpd-1</b> is coordinated in a κ³ fashion. The complex exhibits a moderate activation of N₂ which enables its protonation under retention of the pentaphosphine ligation. Replacement of dmpm by the sterically more demanding coligand dppm is found to hamper coordination of N₂ and leads to [Mo­(trpd-1)­(dppm)], the first structurally characterized five-coordinate Mo(0) complex with a phosphine-only ligand sphere. Employing the ligand <b>trpd-2</b> along with the diphosphines dmpm and dppm in an analogous synthetic route results in a mixture of the bis­(dinitrogen) complexes <i>trans</i>-[Mo­(N₂)₂(κ²-trpd-2)­(diphosphine)] and <i>trans</i>-[Mo­(N₂)₂(<i>iso-</i>κ²-trpd-2)­(diphosphine)] where the tripod ligand <b>trpd-2</b> coordinates with two phosphine arms and one phosphine group (PPh₂ or PⁱPr₂, respectively) is free. Similar results are obtained with the pure alkyl- and arylphosphine tripod ligands H–C­(CH₂PⁱPr₂)₃ (<b>trpd-3</b>) and H–C­(CH₂PPh₂)₃ (<b>tdppmm</b>), leading to <i>trans</i>-[Mo­(N₂)₂(κ²-trpd-3)­(diphos)] and <i>trans</i>-[Mo­(N₂)₂(κ²-tdppmm)­(dmpm)], respectively. The electronic and steric reasons for the experimental findings are considered, and the implications of the results for the area of synthetic nitrogen fixation with molybdenum phosphine systems are discussed

Expansion of Antimonato Polyoxovanadates with Transition Metal Complexes: (Co(N₃C₅H₁₅)₂)₂[{Co(N₃C₅H₁₅)₂}V₁₅Sb₆O₄₂(H₂O)]·5H₂O and (Ni(N₃C₅H₁₅)₂)₂[{Ni(N₃C₅H₁₅)₂}V₁₅Sb₆O₄₂(H₂O)]·8H₂O

Two new polyoxovanadates (Co­(N₃C₅H₁₅)₂)₂[{Co­(N₃C₅H₁₅)₂}­V₁₅Sb₆O₄₂(H₂O)]·5H₂O (<b>1</b>) and (Ni­(N₃C₅H₁₅)₂)₂[{Ni­(N₃C₅H₁₅)₂}­V₁₅Sb₆O₄₂(H₂O)]·8H₂O (<b>2</b>) (N₃C₅H₁₅ = <i>N</i>-(2-aminoethyl)-1,3-propanediamine) were synthesized under solvothermal conditions and structurally characterized. In both structures the [V₁₅Sb₆O₄₂(H₂O)]^6– shell displays the main structural motif, which is strongly related to the {V₁₈O₄₂} archetype cluster. Both compounds crystallize in the triclinic space group <i>P</i>1̅ with <i>a</i> = 14.3438(4), <i>b</i> = 16.6471(6), <i>c</i> = 18.9186(6) Å, α = 87.291(3)°, β = 83.340(3)°, γ = 78.890(3)°, and <i>V</i> = 4401.4(2) ų (<b>1</b>) and <i>a</i> = 14.5697(13), <i>b</i> = 15.8523(16), <i>c</i> = 20.2411(18) Å, α = 86.702(11)°, β = 84.957(11)°, γ = 76.941(11)°, and <i>V</i> = 4533.0(7) ų (<b>2</b>). In the structure of <b>1</b> the [V₁₅Sb₆O₄₂(H₂O)]^6– cluster anion is bound to a [Co­(N₃C₅H₁₅)₂]²⁺ complex via a terminal oxygen atom. In the Co²⁺-centered complex, one of the amine ligands coordinates in tridentate mode and the second one in bidentate mode to form a strongly distorted CoN₅O octahedron. Similarly, in compound <b>2</b> an analogous NiN₅O complex is joined to the [V₁₅Sb₆O₄₂(H₂O)]^6– anion via the same attachment mode. A remarkable difference between the two compounds is the orientation of the noncoordinated propylamine group leading to intermolecular Sb···O contacts in <b>1</b> and to Sb···N interactions in <b>2</b>. In the solid-state lattices of <b>1</b> and <b>2</b>, two additional [M­(N₃C₅H₁₅)₂]²⁺ complexes act as countercations and are located between the [{M­(N₃C₅H₁₅)₂}­V₁₅Sb₆O₄₂(H₂O)]^4– anions. Between the anions and cations strong N–H···O hydrogen bonds are observed. In both compounds the clusters are stacked along the <i>b</i> axis in an ABAB fashion with cations and water molecules occupying the space between the clusters. Magnetic characterization demonstrates that the Ni²⁺ and Co²⁺ cations do not significantly couple with the <i>S</i> = 1/2 vanadyl groups. The susceptibility data can be successfully reproduced assuming a distorted ligand field for the Co²⁺ ions (<b>1</b>) and an <i>O</i>_<i>h</i>-symmetric Ni²⁺ ligand field (<b>2</b>)

Bonding and Activation of N₂ in Mo(0) Complexes Supported by Hybrid Tripod Ligands with Mixed Dialkylphosphine/Diarylphosphine Donor Groups: Interplay of Steric and Electronic Factors

Molybdenum dinitrogen complexes are presented which are supported by novel hybrid tripod ligands of the type Me-C­(CH₂PPh₂)₂(CH₂PⁱPr₂) (<b>trpd-1</b>) and H–C­(CH₂PPh₂)­(CH₂PⁱPr₂)₂ (<b>trpd-2</b>) having mixed dialkylphosphine/diarylphosphine donor groups. Reaction of the ligand <b>trpd-1</b> with [MoI₃(thf)₃] followed by sodium amalgam reduction in the presence of the dppm gives the dinitrogen complex [Mo­(N₂)­(trpd-1)­(dmpm)] where <b>trpd-1</b> is coordinated in a κ³ fashion. The complex exhibits a moderate activation of N₂ which enables its protonation under retention of the pentaphosphine ligation. Replacement of dmpm by the sterically more demanding coligand dppm is found to hamper coordination of N₂ and leads to [Mo­(trpd-1)­(dppm)], the first structurally characterized five-coordinate Mo(0) complex with a phosphine-only ligand sphere. Employing the ligand <b>trpd-2</b> along with the diphosphines dmpm and dppm in an analogous synthetic route results in a mixture of the bis­(dinitrogen) complexes <i>trans</i>-[Mo­(N₂)₂(κ²-trpd-2)­(diphosphine)] and <i>trans</i>-[Mo­(N₂)₂(<i>iso-</i>κ²-trpd-2)­(diphosphine)] where the tripod ligand <b>trpd-2</b> coordinates with two phosphine arms and one phosphine group (PPh₂ or PⁱPr₂, respectively) is free. Similar results are obtained with the pure alkyl- and arylphosphine tripod ligands H–C­(CH₂PⁱPr₂)₃ (<b>trpd-3</b>) and H–C­(CH₂PPh₂)₃ (<b>tdppmm</b>), leading to <i>trans</i>-[Mo­(N₂)₂(κ²-trpd-3)­(diphos)] and <i>trans</i>-[Mo­(N₂)₂(κ²-tdppmm)­(dmpm)], respectively. The electronic and steric reasons for the experimental findings are considered, and the implications of the results for the area of synthetic nitrogen fixation with molybdenum phosphine systems are discussed

Expansion of Antimonato Polyoxovanadates with Transition Metal Complexes: (Co(N₃C₅H₁₅)₂)₂[{Co(N₃C₅H₁₅)₂}V₁₅Sb₆O₄₂(H₂O)]·5H₂O and (Ni(N₃C₅H₁₅)₂)₂[{Ni(N₃C₅H₁₅)₂}V₁₅Sb₆O₄₂(H₂O)]·8H₂O

Two new polyoxovanadates (Co­(N₃C₅H₁₅)₂)₂[{Co­(N₃C₅H₁₅)₂}­V₁₅Sb₆O₄₂(H₂O)]·5H₂O (<b>1</b>) and (Ni­(N₃C₅H₁₅)₂)₂[{Ni­(N₃C₅H₁₅)₂}­V₁₅Sb₆O₄₂(H₂O)]·8H₂O (<b>2</b>) (N₃C₅H₁₅ = <i>N</i>-(2-aminoethyl)-1,3-propanediamine) were synthesized under solvothermal conditions and structurally characterized. In both structures the [V₁₅Sb₆O₄₂(H₂O)]^6– shell displays the main structural motif, which is strongly related to the {V₁₈O₄₂} archetype cluster. Both compounds crystallize in the triclinic space group <i>P</i>1̅ with <i>a</i> = 14.3438(4), <i>b</i> = 16.6471(6), <i>c</i> = 18.9186(6) Å, α = 87.291(3)°, β = 83.340(3)°, γ = 78.890(3)°, and <i>V</i> = 4401.4(2) ų (<b>1</b>) and <i>a</i> = 14.5697(13), <i>b</i> = 15.8523(16), <i>c</i> = 20.2411(18) Å, α = 86.702(11)°, β = 84.957(11)°, γ = 76.941(11)°, and <i>V</i> = 4533.0(7) ų (<b>2</b>). In the structure of <b>1</b> the [V₁₅Sb₆O₄₂(H₂O)]^6– cluster anion is bound to a [Co­(N₃C₅H₁₅)₂]²⁺ complex via a terminal oxygen atom. In the Co²⁺-centered complex, one of the amine ligands coordinates in tridentate mode and the second one in bidentate mode to form a strongly distorted CoN₅O octahedron. Similarly, in compound <b>2</b> an analogous NiN₅O complex is joined to the [V₁₅Sb₆O₄₂(H₂O)]^6– anion via the same attachment mode. A remarkable difference between the two compounds is the orientation of the noncoordinated propylamine group leading to intermolecular Sb···O contacts in <b>1</b> and to Sb···N interactions in <b>2</b>. In the solid-state lattices of <b>1</b> and <b>2</b>, two additional [M­(N₃C₅H₁₅)₂]²⁺ complexes act as countercations and are located between the [{M­(N₃C₅H₁₅)₂}­V₁₅Sb₆O₄₂(H₂O)]^4– anions. Between the anions and cations strong N–H···O hydrogen bonds are observed. In both compounds the clusters are stacked along the <i>b</i> axis in an ABAB fashion with cations and water molecules occupying the space between the clusters. Magnetic characterization demonstrates that the Ni²⁺ and Co²⁺ cations do not significantly couple with the <i>S</i> = 1/2 vanadyl groups. The susceptibility data can be successfully reproduced assuming a distorted ligand field for the Co²⁺ ions (<b>1</b>) and an <i>O</i>_<i>h</i>-symmetric Ni²⁺ ligand field (<b>2</b>)