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1.
Polyol Metal Complexes. 27. Bis-Diolato Antimonates(III ) with Guanosine as the Diol The complex anions of K3[SbIII(Guo1,2′,3′H?3)2] · 10 H2O ( 1 ) and [Co(NH3)6][SbIII(Guo1,2′,3′H?3)2] · 9 H2O ( 2 ) are four-coordinate homoleptic bis(diolato)antimonate(III ) species. The guanosine trianions act as carbohydrate ligands through their cis-furanoidic ribosyl moiety, thus forming no nucleobase–metal bonds.  相似文献   

2.
Polyol Metal Complexes. 25. rac-Mannose, rac-Arabitol and L -Threitol as Deprotonated Ligands in Ferrates(III ) Ba2[Fe2(β-rac-ManfH?5)2] · 12H2O ( 1 ), Sr4[Fe4(rac-Arab1,2,3,5H?4)4(OH)2]CO3 · 33 H2O ( 2 ), and Ba2[Fe2(L-ThreH?4)2(OH)2] · 12.5 H2O ( 3 ) (Man = mannose, Arab = arabitol, Thre = threitol) have been crystallized from alkaline aqueous solution. Crystal structure analysis revealed dinuclear ferrate(III ) ions for 1 and 3 , the former being a Ci-symmetrical homoleptic ferric complex with pentadentate pentaanions derived from racemic β-mannofuranose. In 3 , besides tetradentate L -threitolato ligands, there is one terminal hydroxo ligand at each ferric center. Hydroxo ligands are also present in the Ci-symmetrical hexaanions of 2 , which are tetranuclear planar entities built up from four edge-sharing FeO6 octahedra. However arabitol is a pentitol, the tetraanionic ligands are only tetradentate for steric reasons.  相似文献   

3.
Polyol Metal Complexes. 35 [1] Diolato Silicate and Germanate Ions from Aqueous Solution Hydrated lithium salts of monoanionic bis(diolato)‐hydroxo complexes of silicon and germanium have been crystallized from alkaline aqueous solutions. The isotypic compounds Li[E(AnErytH–2)2(OH)] · H2O, E = Si ( 1 ) or Ge ( 2 ), AnErytH–2 = anhydroerythritol dianions, were obtained in the form of pseudomeroedric twins, a fact that may be traced back to orthorhombic pseudosymmetry of the monoclinic crystals. With potassium as the counterion, anhydrous crystals of K[Si(AnErytH–2)2(OH)] were grown by evaporating the solvent almost entirely from the aqueous mother liquors.  相似文献   

4.
The complex carbonates of iron(III) are shown to be anionic in nature. The solutions containing these complexes show a maximum absorbance at 460 nm. The complex carbonates of iron(III), viz., (i) K6[Fe2(OH)2(CO3)5] · H2O, — (ii) Na2[Fe3O2(OH)3(CO3)2], — (iii) K[Co(NH3)6]2[Fe3(OH)4(CO3)6], — (iv) K5[Co(NH3)6]3[Fe3(OH) 4(CO3)6]2, — (v) K[Co(NH3)6][Fe2(OH)4(CO3)3], and (vi) NH4[Co(NH3)6][Fe2(OH)4(CO3)3] are isolated and studied by thermogravimetry. The infrared spectra of these compounds are recorded and probable band assignments made. Besides, the reaction between KHCO3 and Fe(NO3)3 was studied through chemical and physicochemical methods.  相似文献   

5.
Polyol Metal Complexes. XIII. Na2[Be(C4H6O3)2] · 5H2O and Na2[Pb(C4H6O3)2] · 3H2O – Two Homoleptic Bis Polyolato Metallates with Beryllium and with Lead Na2[Be(C4H6O3)2] · 5H2O ( 1 ) and Na2[Pb(C4H6O3)2] · 3H2O ( 2 ) crystallize from concentrated, alkaline aqueous solutions. The polyol anhydroerythritol is deprotonated twice in the mononuclear, homoleptic complex anions. The preference of beryllium for the binding of cis-furanoid diols is shown. In 2 , a stereochemically active lone pair at the central atom is the reason for the construction of low dimensional aggregates from three plumbate and three sodium ions.  相似文献   

6.
Polyol Metal Complexes.471) Crystalline D ‐Mannose‐Copper Complexes from Fehling Solutions Blue, unstable crystals of K3[Cu5(β‐D ‐Manp)4H—13] · α‐D ‐Manp · 16.5 H2O ( 1 ), which contain a pentanuclear cupric complex of the reducing sugar D ‐mannose in its β‐pyranose form (β‐D ‐Manp), have been obtained from ice‐cold aqueous alkaline solutions. The homoleptic pentacuprate contains bridging mannopyranose ligands, which are charged 4— and 2.5—. Addition of ethylenediamine (en) to such Fehling solutions yields N, N′‐Bis(β‐D ‐mannopyranosyl)‐ethylenediamine (L) as a condensation product of the diamine and mannopyranose. Crystals of [(en)2Cu7(β‐D ‐Manp1, 2, 3, 4H—4)2(L2, 3, 4H—3)2] · 26.6 H2O ( 2 ) could be isolated. The heptanuclear cupric complex is a structural derivative of the homoleptic mannose complex.  相似文献   

7.
Investigation of the Hydrolytic Build‐up of Iron(III)‐Oxo‐Aggregates The synthesis and structures of five new iron/hpdta complexes [{FeIII4(μ‐O)(μ‐OH)(hpdta)2(H2O)4}2FeII(H2O)4]·21H2O ( 2 ), (pipH2)2[Fe2(hpdta)2]·8H2O ( 4 ), (NH4)4[Fe6(μ‐O)(μ‐OH)5(hpdta)3]·20.5H2O ( 5 ), (pipH2)1.5[Fe4(μ‐O)(μ‐OH)3(hpdta)2]·6H2O ( 7 ), [{Fe6(μ3‐O)2(μ‐OH)2(hpdta)2(H4hpdta)2}2]·py·50H2O ( 9 ) are described and the formation of these is discussed in the context of other previously published hpdta‐complexes (H5hpdta = 2‐Hydroxypropane‐1, 3‐diamine‐N, N, N′, N′‐tetraacetic acid). Terminal water ligands are important for the successive build‐up of higher nuclearity oxy/hydroxy bridged aggregates as well as for the activation of substrates such as DMA and CO2. The formation of the compounds under hydrolytic conditions formally results from condensation reactions. The magnetic behaviour can be quantified analogously up to the hexanuclear aggregate 5 . The iron(III) atoms in 1 ‐ 7 are antiferromagnetically coupled giving rise to S = 0 spin ground states. In the dodecanuclear iron(III) aggregate 9 we observe the encapsulation of inorganic ionic fragments by dimeric{M2hpdta}‐units as we recently reported for AlIII/hpdta‐system.  相似文献   

8.
Crystallographic analysis has provided evidence for single cation frameworks formed from preordered cation positions in the individual building blocks (modules) constituting the basis of structures. We propose to call this phenomenon coherence assembly. According to the mechanical wave concept of the crystalline state, coherence assembly dictates the rules of mutual packing of “rigid” structural fragments. This study investigates the typical structures of heteropolyniobates: Na12[Ti2O2][SiNb12O40]·4H2O (I), menezesite Ba2MgZr4[BaNb12O42]·12H2O (II), and the menezesite-isostructural aspedamite □12(Fe3+,Fe2+)3Nb4·[Th(Nb,Fe3+)12O42]·(H2O,OH)12 (III).  相似文献   

9.
Three new hexanuclear Fe(III) coordination wheels [Fe6Cl6(L1)6]·5(MeCN) (1), [Na0.5Fe6Cl6(L1)6](N3)0.5·4.5(MeCN) (2), and [Fe6Cl6(L2)6]·2(MeCN) (3) have been synthesized with new prepared amino-acetonitrile derivatives 2-[bis(2-hydroxyethyl)amino]acetonitrile hydrochloride (H2L1) and 3-[bis(2-hydroxyethyl)amino]propanenitrile hydrochloride (H2L2). They were structurally characterized by single-crystal X-ray diffraction. Mößbauer spectroscopy and magnetic susceptibility measurements indicate dominant antiferromagnetic behavior between the Fe(III) centers.  相似文献   

10.
The FeCl2-Na2SO3-H2O system was studied along seven sections with the molar ratios Na2SO3: FeCl2 = 5: 1, 5: 2, 5: 3, 5: 4, 5: 5, 5: 10, and 5: 15, including six points on each section where pH ranges from 1.5 to 4.0 in 0.5 steps. Equal-undersedimentation lines for cations and anions were plotted. The iron(II) system forms sodium ferrisulfites NaFe5O0.5(SO3)5 · 5H2O, NaHFe5(SO3)6 · 5H2O, Na2Fe5(SO3)6 · 4H2O, and NaHFe2(SO3)3; the iron(III) system forms Na2Fe6(SO3)7 · 10H2O. The regions where these compounds sediment were demarcated, and their characterizations were carried out.  相似文献   

11.
Reaction of CeCl3·7H2O with Na2(oda) (oda = O(CH2CO2)22— oxydiacetate) in a 2:3 ratio gives the neutral cerium(III) complex [Ce2(oda)3(H2O)3]·9H2O ( 1 ). Treatment of a 1:3 mixture of CeCl3·7H2O and H2oda in water with 4 molar equivalents of NaOH also gives 1 but, with a larger excess of NaOH, the tri‐sodium salt Na3[Ce(oda)3]·9H2O ( 2 ) is isolated. Formation of a tri‐ammonium analogue of 2 can be achieved by neutralisation of an aqueous solution of CeCl3·7H2O and H2(oda) in a 1:3 ratio by NH4OH, giving (NH4)3[Ce(oda)3]·7H2O ( 3 ). Use of the cerium(IV) reagent (NH4)2[Ce(NO3)6] with Na2(oda) results in reduction to cerium(III) under ambient conditions and isolation of 1 . However, in the absence of light this reaction yields crystals of the novel cerium(IV) heterobimetallic [Ce(oda)3Na4(NO3)2] ( 4 ). Each of these complexes exhibit a 3‐D network structure having a common nine‐coordinate [Ce(oda)3]n— (n = 2 or 3) subunit, irrespective of the oxidation state of cerium. In 1 , six [Ce(oda)3]3— anions are connected, through bridging bidentate carboxylates, to a second Ce3+ site further coordinated by three water molecules. In contrast, the ammonium salt 2 , displays isolated [Ce(oda)3]3— anions, devoid of further carboxylate bonding, but enmeshed within a network of hydrogen‐bonded NH4+ cations and water molecules. The remarkable structure of 4 consists of infinite 2‐D sheets of [Na2(NO3)]+ pillared by [Ce(oda)3]2— units, the connectivity arising by multidentate nitrate and carboxylate bridging.  相似文献   

12.
The iron-sulfur nitrosyl complexes A[Fe4S3(NO)7], where A=Na+, NH4 +, or N(Bu n )4 +, and B2[Fe2S2(NO)4], where B=Na+, Cs+, or N(Bun)4 +, were synthesized. Their structures and properties were studied by X-ray diffraction analysis, Mössbauer spectroscopy, and cyclic voltammetry. The effect of the crystal packing on the geometry of the tetranuclear NH4[Fe4S3(NO)7]·H2O and binuclear Cs2[Fe2S2(NO)4]·2H2O complexes was analyzed. The changes in the Fe57 Mössbauer spectral parameters of the anion in the B2[Fe2S2(NO)4] series depend on the size of the B cation and agree with variations in the structural parameters of the Fe[S2(NO)2] chromophores as well as in the stretching vibrations of the NO groups caused by changes in intermolecular contacts. The presence of electronic states delocalized through the Fe?Fe bonds explains the fact that the electronic states of the Fea(S3NO) and Feb(S2(NO)2) chromophores in the [Fe4S3(NO)7]? anion are nearly identical. The binuclear clusters are unstable upon storage in the solid phase and decompose in solutions to form the tetranuclear [Fe4S3(NO)7]? complexes, sulfur, and nitrogen oxides. The redox properties of the [Fe4S3(NO)7]? and [Fe2S2(NO4)]2? anions in CH3CN and THF solutions were studied. The mechanism of reduction of the anion in the tetranuclear cluster is proposed.  相似文献   

13.
Complex Hydroxides of Chromium: Na9[Cr(OH)6]2(OH)3 · 6 H2O and Na4[Cr(OH)6]X · H2O (X = Cl, (S2)1/2) – Synthesis, Crystal Structure, and Thermal Behaviour Green plate‐like crystals of Na9[Cr(OH)6]2(OH)3 · 6 H2O (triclinic, P1, a = 872.9(1) pm, b = 1142.0(1) pm, c = 1166.0(1) pm, α = 74.27(1)°, β = 87.54(1)°, γ = 70.69(1)°) are obtained upon slow cooling of a hot saturated solution of CrIII in conc. NaOH (50 wt%) at room temperature. In the presence of chloride or disulfide the reaction yields green prismatic crystals of Na4[Cr(OH)6]Cl · H2O (monoclinic, C2/c, a = 1138.8(2) pm, b = 1360.4(1) pm, c = 583.20(7) pm, β = 105.9(1)°) or green elongated plates of Na4[Cr(OH)6](S2)1/2 · H2O (monoclinic, P21/c, a = 580.8(1) pm, b = 1366.5(3) pm, c = 1115.0(2) pm, β = 103.71(2)°), respectively. The latter compounds crystallize in related structures. All compounds can be described as distorted cubic closest packings of the anions and the crystal water molecules with the cations occupying octahedral sites in an ordered way. The thermal decomposition of the compounds was investigated by DSC/TG or DTA/TG and high temperature X‐ray powder diffraction measurements. In all cases the final decomposition product is NaCrO2.  相似文献   

14.
The title compound, tricaesium sodium iron(III) μ3‐oxido‐hexa‐μ2‐sulfato‐tris[aquairon(III)] pentahydrate, Cs2.91Na1.34Fe3+0.25[Fe3O(SO4)6(H2O)3]·5H2O, belongs to the family of Maus's salts, K5[Fe3O(SO4)6(H2O)3]·6H2O, which is based on the triaqua‐μ3‐oxido‐hexa‐μ‐sulfato‐triferrate(III) anion, [Fe3O(SO4)6(H2O)3]5−, with Fe in a characteristically distorted octahedral coordination environment, sharing a common corner via an oxide O atom. Cs in four different cation sites, Na in three different cation sites and five water molecules link the anions in three dimensions and set up a crystal structure in which those parts parallel to (001) and within 0.05 < z < 0.95 have a distinct trigonal pseudosymmetry, whereas the cation arrangement and bonding near z∼ 0 generate a clear‐cut noncentrosymmetric polar edifice with the monoclinic space group C2. The structure shows some cation disorder in the region near z ∼ , where one Na atom in octahedral coordination is partly substituted by Fe3+, and a Cs atom is substituted by small amounts of Na on a separate nearby site. One Na atom, located on a twofold axis at z = 0 and tetrahedrally coordinated by four sulfate O atoms of two [Fe3O(SO4)6(H2O)3]5− units, plays a key role in generating the noncentrosymmetric structure. Three of the seven different cation sites are on twofold axes (one Na+ site and two Cs+ sites), and all other atoms of the structure are in general positions.  相似文献   

15.
An Anionic Oxohydroxo Complex with Bismuth(III): Na6[Bi2O2(OH)6](OH)2 · 4H2O Colourless, plate‐like, air sensitive crystals of Na6[Bi2O2(OH)6](OH)2 · 4H2O are obtained by reaction of Bi2O3 or Bi(NO3)3 · 5H2O in conc. NaOH (58 wt %) at 200 °C followed by slow cooling to room temperature. The crystal structure (triclinic, P 1¯, a = 684.0(2), b = 759.8(2), c = 822.7(2) pm, α = 92.45(3)°, ß = 90.40(3)°, γ = 115.60(2)°, Z = 1, R1, wR2 (all data), 0, 042, 0, 076) contains dimeric, anionic complexes [Bi2O2(OH)6]4— with bismuth in an ψ1‐octahedral coordination of two oxo‐ and three hydroxo‐ligands. The thermal decomposition was investigated by DSC/TG or DTA/TG and high temperature X‐ray powder diffraction measurements. In the final of three steps the decomposition product is Na3BiO3.  相似文献   

16.
New Heteropolyanions of the M2X2W20 Structure Type with Antimony(III) as a Heteroatom The syntheses of two new heteropolyanions of the M2X2W20 structure type are presented. They are characterized by X‐ray structure analysis and vibrational spectra. Na6(NH4)4[Zn2(H2O)6(WO2)2(SbW9O33)2]·36H2O (1) is monoclinic (P21/n) with a = 12.873(3)Å, b = 25.303(4)Å, c = 15.975(4)Å and β = 91.99(3)°. Na10[Mn2(H2O)6(WO2)2(SbW9O33)2]·40H2O (2) also crystallizes in the space group P21/n with a = 12.892(3)Å, b = 25.219(5)Å, c = 16.166(3)Å and β = 94.41(3)°. Both polyanions are isostructural to anions of this structure type containing other heteroatoms. They are built up by two β‐B‐SbW9 fragments, which are derived from defect structures of the Keggin anion. These subÍunits are connected by two formal WO2 groups with further stabilization by addition of two M(H2O)3 groups (M = ZnII, MnII, FeIII, CoII) leading to the M2X2W20‐type heteropolytungstates.  相似文献   

17.
Amido Complexes of Manganese(II). Syntheses and Crystal Structures of [Mn(NPh2)2(THF)]2 and Na2[Mn(NPh2)4] · 2 C7H8 The silylated amido complex [Mn{N(SiMe3)2}2 · (THF)] reacts in toluene solution with diphenylamine under ligand exchange to form the diphenylamido complex [Mn(NPh2)2(THF)]2 ( 1 ), which forms orange-red columnar crystals. 1 reacts in THF solution with NaN(SiMe3)2 and after crystallization from toluene yellow-orange Na2[Mn(NPh2)4] · 2 C7H8 ( 2 ) is obtained. According to the crystal structure analyses the manganese atoms in 1 (space group P21/c, Z = 2) are linked via the N atoms of two of the NPh2 groups to form centrosymmetric Mn2N2 four-membered rings with Mn–N bonds of almost the same length. 2 (space group I41/a, Z = 4) forms a three-dimensional space-lattice structure, which arises from ”︁inner solvation”︁”︁ of the sodium atoms with the phenyl rings of the NPh2 group.  相似文献   

18.
High resolution vanadium K-edge spectra (XANES) have been measured using the synchrotron radiation available at the Institute of Nuclear Physics of the Academy of Sciences of the U.S.S.R., Novosibirsk. The compounds investigated include anions of oxalic acid (ox), ethylenediaminetetraacetic acid (EDTA) and nitrilotriacetic acid (NTA) as ligands: (NH4)3[VO2(ox)2]·2H2O, (NH4)2 [VO(ox)2H2O]·H2O, Na3[VO2(EDTA)]·9H2O, Na2[VO(EDTA)]·3H2O, Na[V(EDTA)]·3H2O, Na3[V2O3(NTA)2]·6H2O, Ba[VO(NTA)H2O]2·2H2O and Na3[V(NTA)2]. The vanadium oxidation states in these compounds cover the region between +5 and +3. The object of this investigation is to obtain further information about the effect of bonding and coordination geometry on the details of the absorption spectra, especially on the intensity and position of a well defined pre-edge absorption peak in most of the compounds.  相似文献   

19.
The compounds (NMe4)5[As2Mo8V4AsO40] · 3 H2O 2a , (NH4)21[H3Mo57V6(NO)6O183(H2O)18] · 65 H2O 3a , (NH2Me2)18(NH4)6[Mo57V6(NO)6O183(H2O)18] · 14 H2O 3b and (NH4)12[Mo36(NO)4O108(H2O)16] · 33 H2O 4a ( 3a and 4a were not correctly reported in the literature regarding to their composition, structures and the oxidation states of the metal centres) which contain large isolated anionic species, have been prepared (among them 3a, 3b , and 4a in rather high yield) and characterized by complete crystal structure analysis as well as IR/Raman, UV/VIS/NIR, ESR spectroscopy and magnetic susceptibility measurements, redox titrations, bond valence sum calculations, elemental analyses and thermogravimetric studies. Perspectives for polyoxometalate chemistry referring to the synthesis of “extremely” large nanoscaled species are discussed, together with the occurrence of a large transferable {Mo17} building block in the compounds 3a, 3b and 4a which also exists in the corresponding iron compound Na3(NH4)12[H15Mo57Fe6(NO)6O183(H2O)18] · 76 H2O 7a .  相似文献   

20.
Novel mixed salts of the paratungstate anion Na2(NH4)8[H2W12O42]·12H2O (1) and Na7.5K2.5[H2W12O42]··22.2H2O (2) are obtained by slow concentration of tungstate solutions and characterized by single crystal X-ray diffraction.  相似文献   

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