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Journal of Structural Chemistry - Derivatives of tris(4-fluorophenyl)antimony (4-FC6H4)3Sb(OC6H3F2-2,4)2 (1), (4-FC6H4)3Sb[OC(O)C6H3F2-2,5]2 (2) and (4-FC6H4)3Sb[OC(O)C≡CPh]2 (3) are prepared...  相似文献   

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Aryl and Aryne Complexes of Group Six Transition Metals. Preparation of [Mo(p-C6H4CH3)6(Li · OC4H10)3] und [W(p-C6H4CH3)4(C6H3CH3)2(Li · OC4H10)4] and NMR Spectroscopic Investigation of the W Complex Molybdenum(V) chloride reacts with an etheral solution of p-tolyllithium (molar ratio 1:10) to yield a yellow, strongly paramagnetic hexatolylo complex ([MoTol6(Li · S)3]1) (μeff = 3.51 B.M.), while from tungsten(V) bromide and p-tolyllithium (molar ratio 1:11) a blackish violet, diamagnetic complex [WTol4Tn2(Li · S)4] is formed, containing two tolylene or tolyne groups for ligands. The 1H-NMR spectrum points to the Tol-ligands being influenced by the methyl groups of the Tn-ligands.  相似文献   

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The first crystallographically characterized molybdenum(vi) selenoether complex [Mo(2)O(4)(OC(3)H(6)SeC(3)H(6)O)(2)] and its thioether analogue [Mo(2)O(4)(OC(3)H(6)SC(3)H(6)O)(2)] were synthesised. Their structural, electrochemical and oxygen atom transfer properties are compared. This is relevant for the molybdenum cofactors of the DMSO reductase family where the coordination of the active site metal occurs through O (serine/aspartate), S (cysteine) or Se (selenocysteine). Both structures are almost identical except for those parameters that are directly derived from the different sizes of the varied ligand atoms (Se and S). No trans influence was observed. The metal centered redox process (Mo(V)<-->Mo(VI)) is at slightly lower voltage for the sulfur than for the selenium complex. The selenium compound catalyses the oxygen atom transfer from DMSO to PPh(3) by a different mechanism and at a higher rate than the sulfur compound, which is an indication that cysteine and selenocysteine might be used for a purpose in the different molybdenum and tungsten cofactors.  相似文献   

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NO[Al(OC(CF(3))(2)Ph)(4)] 1 and NO[Al(OC(CF(3))(3))(4)] 2 were obtained by the metathesis reaction of NO[SbF(6)] and the corresponding Li[Al(OR)(4)] salts in liquid sulfur dioxide solution in ca 40% (1) and 85% (2) isolated yield. 1 and 2, as well as Li[NO(3)] and N(2)O, were also given by the reaction of an excess of mixture of (90 mol%) NO, (10 mol%) NO(2) with Li[Al(OR)(4)] followed by extraction with SO(2). The unfavourable disproportionation reaction of 2NO(2)(g) to [NO](+)(g) and [NO(3)](-)(g)[DeltaH degrees = +616.2 kJ mol(-1)] is more than compensated by the disproportionation energy of 3NO(g) to N(2)O(g) and NO(2)(g)[DeltaH degrees =-155.4 kJ mol(-1)] and the lattice energy of Li[NO(3)](s)[U(POT)= 862 kJ mol(-1)]. Evidence is presented that the reaction proceeds via a complex of [Li](+) with NO, NO(2)(or their dimers) and N(2)O. NO(2) and Li[Al(OC(CF(3))(3))(4)] gave [NO(3)(NO)(3)][Al(OC(CF(3))(3))(4)](2), NO[Al(OC(CF(3))(3))(4)] and (NO(2))[Al(OC(CF(3))(3))(4)] products. The aluminium complex [Li[AlF(OC(CF(3))(2)Ph)(3)]](2) 3 was prepared by the thermal decomposition of Li[Al(OC(CF(3))(2)Ph)(4)]. Compounds 1 and 3 were characterized by single crystal X-ray structural analyses, 1-3 by elemental analyses, NMR, IR, Raman and mass spectra. Solid 1 contains [Al(OC(CF(3))(2)Ph)(4)](-) and [NO](+) weakly linked via donor acceptor interactions, while in the SO(2) solution there is an equilibrium between the associated [NO](+)[Al(OC(CF(3))(2)Ph)(4)](-) and separated solvated ions. Solid 2 contains essentially ionic [NO](+) and [Al(OC(CF(3))(3))(4)](-). Complex 3 consists of two [Li[AlF(OC(CF(3))(2)Ph)(3)]] units linked via fluorine lithium contacts. Compound 1 is unstable in the SO(2) solution and decomposes to yield [AlF(OC(CF(3))(2)Ph)(3)](-), [(PhC(CF(3))(2)O)(3)Al(mu-F)Al(OC(CF(3))(2)Ph)(3)](-) anions as well as (NO)C(6)H(4)C(CF(3))(2)OH, while compound 2 is stable in liquid SO(2). The [small nu](NO(+)) in 1 and [NO](+)(toluene)[SbCl(6)] are similar, implying similar basicities of [Al(OC(CF(3))(2)Ph)(4)](-) and toluene.  相似文献   

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{[2‐FC6H4C(NSiMe3)2Li]4Li2O} — Formation of an Oxygen‐centred Cage From the reaction of [2‐FC6H4C(NSiMe3)2Li]2·OEt2 ( 1 ) with water containing toluene the oxygen‐centred cage {[2‐FC6H4C(NSiMe3)2Li]4Li2O} ( 2 ) was obtained. The formation of the cage structure, which contains a central Li6O‐unit, can be explained by using the laddering principle.  相似文献   

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A series of sterically varied aryl alcohols H-OAr [OAr = OC6H5 (OPh), OC6H4(2-Me) (oMP), OC6H3(2,6-(Me))2 (DMP), OC6H4(2-Pr(i)) (oPP), OC6H3(2,6-(Pr(i)))2 (DIP), OC6H4(2-Bu(t)) (oBP), OC6H3(2,6-(Bu(t)))2 (DBP); Me = CH3, Pr(i) = CHMe2, and Bu(t) = CMe3] were reacted with LiN(SiMe3)2 in a Lewis basic solvent [tetrahydrofuran (THF) or pyridine (py)] to generate the appropriate "Li(OAr)(solv)x". In the presence of THF, the OPh derivative was previously identified as the hexagonal prismatic complex [Li(OPh)(THF)]6; however, the structure isolated from the above route proved to be the tetranuclear species [Li(OPh)(THF)]4 (1). The other "Li(OAr)(THF)x" products isolated were characterized by single-crystal X-ray diffraction as [Li(OAr)(THF)]4 [OAr = oMP (2), DMP (3), oPP (4)], [Li(DIP)(THF)]3 (5), [Li(oBP)(THF)2]2, (6), and [Li(DBP)(THF)]2, (7). The tetranuclear species (1-4) consist of symmetric cubes of alternating tetrahedral Li and pyramidal O atoms, with terminal THF solvent molecules bound to each metal center. The trinuclear species 5 consists of a six-membered ring of alternating trigonal planar Li and bridging O atoms, with one THF solvent molecule bound to each metal center. Compound 6 possesses two Li atoms that adopt tetrahedral geometries involving two bridging oBP and two terminal THF ligands. The structure of 7 was identical to the previously reported [Li(DBP)(THF)]2 species, but different unit cell parameters were observed. Compound 7 varies from 6 in that only one solvent molecule is bound to each Li metal center of 7 because of the steric bulk of the DBP ligand. In contrast to the structurally diverse THF adducts, when py was used as the solvent, the appropriate "Li(OAr)(py)x" complexes were isolated as [Li(OAr)(py)2]2 (OAr = OPh (8), oMP (9), DMP (10), oPP (11), DIP (12), oBP (13)) and [Li(DBP)(py)]2 (14). Compounds 8-13 adopt a dinuclear, edge-shared tetrahedral complex. For 14, because of the steric crowding of the DBP ligand, only one py is coordinated, yielding a dinuclear fused trigonal planar arrangement. Two additional structure types were also characterized for the DIP ligand: [Li(DIP)(H-DIP)(py)]2 (12b) and [Li2(DIP)2(py)3] (12c). Multinuclear (6,7Li and 13C) solid-state MAS NMR spectroscopic studies indicate that the bulk powder possesses several Li environments for "transitional ligands" of the THF complexes; however, the py adducts possess only one Li environment, which is consistent with the solid-state structures. Solution NMR studies indicate that "transitional" compounds of the THF precursors display multiple species in solution whereas the py adducts display only one lithium environment.  相似文献   

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Molybdenum(II) Halide Clusters with two Alcoholate Ligands: Syntheses and Crystal Structures of (C18H36N2O6Na)2[Mo6Cl12(OCH3)2] and (C18H36N2O6Na)2[Mo6Cl12(OC15H11)2] · 2C4H6O3 . Reaction of Mo6Cl12 with two equivalents of sodium methoxide in the presence of 2,2,2-crypt yields (C18H36N2O6Na)2[Mo6Cl12(OCH3)2] ( 1 ), which can be converted to (C18H36N2O6Na)2[Mo6Cl12(OC15H11)2] · 2C4H6O3 ( 2 ) by metathesis with 9-Anthracenemethanole in propylene carbonate. As confirmed by X-ray single crystal structure determination ( 1 : C2/m, a=25.513(8) Å, b=13.001(3) Å, c=10.128(3) Å, β=100.204(12)°; : C2/c, a=15.580(5) Å, b=22.337(5) Å, c=27.143(8) Å, β=98.756(10)°) the compounds contain anionic cluster units [Mo6ClCl(ORa)2]2? with two alcoholate ligands in terminal trans positions ( 1 : d(Mo—Mo) 2.597(2) Å to 2.610(2) Å, d(Mo—Cli) 2.471(3) Å to 2.493(4) Å, d(Mo—Cla) 2.417(8) Å and 2.427(8) Å, d(Mo—O) 2.006(13) Å; 2 : d(Mo—Mo) 2.599(3) Å to 2.628(3), d(Mo—Cli) 2.468(8) Å to 2.506(7) Å, d(Mo—Cla) 2.444(8) Å and 2.445(7) Å, d(Mo—O) 2.012(19) Å).  相似文献   

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Barium Stannate Powders from Hydrothermal Synthesis and by Thermolysis of Barium‐Tin(IV)‐Glycolates. Synthesis and Structure of [Ba(C2H6O2)4][Sn(C2H4O2)3] and [Ba(C2H6O2)2][Sn(C2H4O2)3]·CH3OH The hydrothermal reaction as well as the microwave assisted hydrothermal reaction of SnO2·aq with barium hydroxide gives Ba[Sn(OH)6] ( 1 ) as powder with bar like particles. Compound 1 of the same morphology can also be isolated from a hydrothermal reaction of [Ba(C2H6O2)4][Sn(C2H4O2)3] ( 3 ). The reaction of SnO2·aq with Ba(OH)2·8H2O in ethylene glycol yields the glycolate [Ba(C2H6O2)4][Sn(C2H4O2)3] ( 3 ), which forms in methanol the solvate [Ba(C2H6O2)2][Sn(C2H4O2)3]·CH3OH ( 4 ). Compounds 1 , 3 and 4 react at different temperatures to BaSnO3 ( 2 ) consisting of powders with different morphologies; because of the grain size of the resulting powders compounds 3 and 4 are suitable as precursor for the fabrication of corresponding ceramics.  相似文献   

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In the title complexes the cis-benzenetrioxide acts as tridentate ligand, allowing for octahedral and unusual tetracapped trigonal prismatic coordination (TECTP).  相似文献   

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Syntheses and Crystal Structures of new Amido- und Imidobridged Cobalt Clusters: [Li(THF)2]3[Co32-NHMes)3Cl6] (1), [Li(DME)3]2[Co184-NPh)33-NPh)12Cl3] (2), [Li(DME)3]2[Co64-NPh)(μ2-NPh)6(PPh2Et)2] (3), and [Li(THF)4][Co83-NPh)62-NPh)3(PPh3)2] (4) The reactions of cobalt(II)-chloride with the lithium-amides LiNHMes and Li2NPh leads to an amido-bridged multinuclear complex [Li(THF)2]3[Co32-NHMes)3Cl6] ( 1 ) as well as to the imido-bridged cobalt cluster [Li(DME)3]2[Co184-NPh)33-NPh)12Cl3] ( 2 ). In the presence of tertiary phosphines two imido-bridged cobalt clusters [Li(DME)3]2[Co64-NPh)(μ2-NPh)6(PPh2Et)2] ( 3 ) and [Li(THF)4][Co83-NPh)62-NPh)3(PPh3)2] ( 4 ) result. The structures of 1 – 4 were characterized by X-ray single crystal structure analysis.  相似文献   

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IntroductionTheexpensionofthecoordinationchemistryofpolyoxomolybdatesisattributedtothesolubilityofthepolyoxometallicanionsinorganicsolventsandcoordi nationabilityofthemascharacteristicmetalligandsinorgano metallicreactions ,forexample ,thestudyofcatalys…  相似文献   

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《Polyhedron》2007,26(9-11):2235-2242
The ligand exchange reaction between Mn(OC(O)CH3)2 and benzoic acid under solvothermal conditions in toluene at 110 °C yields colorless crystals of {Mn5(OC(O)CH3)6(OC(O)C6H5)4} (1). The asymmetric unit of this complex is Mn2.5(OC(O)CH3)3(OC(O)C6H5)2 with each of the three different Mn(II) atoms in 6-fold coordination and one of the benzoate ligands exhibiting the rare μ3-symmetric bridging mode (O–Mn–O angle = 57°). The structure consists of edge-shared Mn12 loops arranged in a honeycomb-like 2D sheet with the acetate ligands displaced slightly out of the plane. The sheets are spaced at 12 Å and linked into a 3D network via weak intersheet interactions. Magnetic susceptibility characterization of 1 indicates antiferromagnetic exchange with a Weiss constant of −165 K and a transition toward ferromagnetic exchange below 10 K corroborated with a finite imaginary component in the variable temperature susceptibility data.  相似文献   

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Single crystals of Sr3Li6M2O11 (M = Nb, Ta) were grown out of a high-temperature Sr(OH)2/LiOH/KOH flux. The single crystal X-ray diffraction data were indexed to the orthorhombic Pmma system, with a = 10.5834(15) A, b = 8.3103(13) A, c = 5.8277(8) A, V = 512.55(13) A(3), and Z = 2 for Sr3Li6Nb2O11 and a = 10.5936(6) A, b = 8.3452(5) A, c = 5.8271(4) A, V = 515.15(6) A(3), and Z = 2 for Sr3Li6Ta2O11. The crystal structure consists of sheets of interconnected SrO8 polyhedra that are separated by M-O layers and an intervening LiO(x) polyhedral framework, representing a new structural type. The M-O layers exhibit a rare occurrence of both five- and six-coordinated M(5+) ions in the same structure. The oxides, upon excitation at 250 nm, exhibit violet emission at room temperature.  相似文献   

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Phosphoraneiminato Acetate Cluster of Copper and Zinc. Crystal Structures of [Cu4(NPEt3)2(O2CCH3)6] and [Zn4(NPEt3)2(O2CCH3)6] The anhydrous acetates of copper(II) and zinc react with the silylated phosphaneimine Me3SiNPEt3 in dichloromethane at 20 °C forming the mixed phosphoraneiminato acetate clusters [Cu4(NPEt3)2(O2CCH3)6] ( 1 ), which forms emerald crystals, and colourless [Zn4(NPEt3)2 · (O2CCH3)6] ( 2 ). In spite of analogous composition the structures of 1 and 2 are completely different. In the asymmetric unit of 1 three copper atoms of an almost isosceles triangle are linked via two nitrogen atoms of the NPEt3 groups to form a trigonal bipyramidal aggregate. One of these three copper atoms is chelated by an acetate group, another one is connected with the fourth copper atom via three μ2‐O2C–CH3 groups. The asymmetric units are associated via a μ2‐O2C–CH3 group and a μ3‐OC(O)CH3 group at a time so that infinite chains result. In 2 two zinc atoms are linked via the nitrogen atoms of the two NPEt3 groups to form an almost centrosymmetric four‐membered ring. Both nitrogen atoms of the four‐membered ring are connected with another zinc atom each. These zinc atoms again are linked with the zinc atoms of the Zn2N2 four‐membered ring via two μ2‐O2C–CH3 groups each and additionally coordinated with a terminal acetate ligand each.  相似文献   

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