The preparation and characterization of the cocrystalline solid-organic sodium ion electrolyte NaClO (DMF) (DMF=dimethylformamide) is described. The crystal structure of NaClO (DMF) reveals parallel channels of Na and ClO ions. Pressed pellets of microcrystalline NaClO (DMF) exhibit a conductivity of 3×10 S cm at room temperature with a low activation barrier to conduction of 25 kJ mol . SEM revealed thin liquid interfacial contacts between crystalline grains, which promote conductivity. The material melts gradually between 55-65 °C, but does not decompose, and upon cooling, it resolidifies as solid NaClO (DMF) , permitting melt casting of the electrolyte into thin films and the fabrication of cells in the liquid state and ensuring penetration of the electrolyte between the electrode active particles.
The preparation of four-coordinate tetramanganese-amide-hydrazide clusters is described. Reaction of Mn(NR(2))(2) (R = SiMe(3)) with N,N'-diphenylhydrazine resulted in the formation of a black intermediary mixture that converted to a four-coordinate tetranuclear "pinned butterfly" cluster, Mn(4)(μ(3)-N(2)Ph(2))(2)(μ-N(2)Ph(2))(μ-NHPh)(2)(THF)(4). This compound was isolated in ~90% yield and identified by single-crystal X-ray diffraction analysis. In pyridine, the THF ligands were replaced, giving the pyridyl complex Mn(4)(μ(3)-N(2)Ph(2))(2)(μ-N(2)Ph(2))(μ-NHPh)(2)(py)(4). Charge counting considerations indicate that the clusters had gained two protons and two electrons in addition to the formative fragments. Isolation of the black mixture was achieved by extraction techniques from a reaction with a decreased loading of hydrazine run at low temperatures with decreased solvent polarity. The black mixture was characterized by FT-IR, UV-vis, and (1)H NMR spectroscopy. In addition, an isolable, colorless dimer, Mn(2)(μ-NHPh)(2)(NR(2))(2)(THF)(2), was present in the mixture and identified by single-crystal X-ray diffraction. These intermediates are discussed in light of possible mechanisms for formation of the tetranuclear cluster.
A mechanistic pathway for the formation of the structurally characterized manganese-amide-hydrazide pinned butterfly complex, Mn4(μ3-PhN-NPh-κ(3)N,N')2(μ-PhN-NPh-κ(2)-N,N')(μ-NHPh)2L4 (L = THF, py), is proposed and supported by the use of labeling studies, kinetic measurements, kinetic competition experiments, kinetic isotope effects, and hydrogen atom transfer reagent substitution, and via the isolation and characterization of intermediates using X-ray diffraction and electron paramagnetic resonance spectroscopy. The data support a formation mechanism whereby bis[bis(trimethylsilyl)amido]manganese(II) (Mn(NR2)2, where R = SiMe3) reacts with N,N'-diphenylhydrazine (PhNHNHPh) via initial proton transfer, followed by reductive N-N bond cleavage to form a long-lived Mn(IV) imido multinuclear complex. Coordinating solvents activate this cluster for abstraction of hydrogen atoms from an additional equivalent of PhNHNHPh resulting in a Mn(II)phenylamido dimer, Mn2(μ-NHPh)2(NR2)2L2. This dimeric complex further assembles in fast steps with two additional equivalents of PhNHNHPh replacing the terminal silylamido ligands with η(1)-hydrazine ligands to give a dimeric Mn2(μ-NHPh)2(PhN-NHPh)2L4 intermediate, and finally, the addition of two additional equivalents of Mn(NR2)2 and PhNHNHPh gives the pinned butterfly cluster.
The long‐time elusive structure of the acid copper(II) salt intermediate in the production of DBX‐1 is presented. The single‐crystal X‐ray shows infinite chains of copper(II) ions complexed by six 5‐nitrotetrazolate anions are aligned along the sixfold axis. Hydronium ions are located on the threefold axis with additional neutral water molecules.
A series of N‐containing heterocyclic compounds have been synthesized using approaches such as the well‐known Knorr synthesis, and a facile N‐alkylation method. This series of compounds includes pyrazole derivatives, tris(2‐benzimidazolylmethyl)amine derivatives, and “pincer” ligands. Characterization methods include 1H NMR, FT‐IR, CHN analyses, UV‐vis spectroscopy, and fluorimetry, while X‐ray crystal structures are reported for most of the compounds. The crystallographic results affirm a 13C NMR method for isomer assignment of substituted pyrazoles.
Mn4(μ-NHPh)4(μ-PhNNPh-κ(2)N,N')2(py)4 () is synthesized via self assembly from dimeric Mn2(μ-NHPh)2(NR2)2 and PhNHNHPh (R = SiMe3). This cluster represents the N-N cleaved version of the previously-reported Mn4(μ-NHPh)2(μ3-PhNNPh-κ(3)N,N')2(μ-PhNNPh-κ(2)N,N')(py)4 "pinned butterfly" cluster (), formally reduced by two hydrogen atoms. Cluster may be converted to by addition of N,N'-diphenylhydrazine as a two-electron reductant.
Polynuclear metal clusters frequently feature geometric structural features not common in traditional coordination chemistry. These structures are of particular interest to bioinorganic chemists studying metallocluster enzymes, which frequently possess remarkably unusual inorganic structures. The structure of the manganese cluster μ-oxido-di-μ-phenoxido-hexa-μ-phenoxido-hexakis(pyridine-κN)hexamanganese(II) pyridine monosolvate, [Mn(CHO)O(CHN)]·CHN or Mn(μ-OPh)(μ-OPh)(μ-O)(Py)·Py, containing an unusual trigonal bipyramidal central oxide, is described. The compound was isolated from a reaction mixture containing bis(trimethylsilylamido)manganese(II) and phenol. The central O atom is presumed to have originated as adventitious water. The molecule crystalizes in a primitive monoclinic crystal system and is presented in the centrosymetric P2/n space group. The molecule possesses crystallographically imposed twofold symmetry, with the central O atom centred on the twofold axis and surrounded by a distorted trigonal bipyramidal arrangement of Mn atoms, which are further bridged by phenoxide ligands, and terminally ligated by pyridine. A pyridine solvent molecule resides nearby, also situated on a crystallographic twofold axis. The cluster is compared to three closely related previously reported structures.
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