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We report the synthesis, post-functionalization, and redox behavior of two organically functionalized aggregates, [V6 O7 (OMe)9 {(OCH2 )3 C-CH2 N3 }] and [V6 O7 (OMe)9 {(OCH2 )3 C-NH2 }]. All twelve μ2 -oxo groups on the edges of the Lindqvist-type {V6 O19 } core were replaced by alkoxo ligands. The absence of a negative charge and the closed organic shell make these neutral mixed-valence compounds very stable towards hydrolysis and well soluble in almost all common organic solvents. These are important advantages over classical POMs. By post-functionalization through copper(I)-catalyzed Huisgen cycloaddition or imine formation, various organic moieties could be introduced. Even a well-soluble trimer composed of three hexanuclear vanadium units connected through an aromatic triimino core was synthesized and studied. The diverse redox behavior, the versatile reactivity, the good stability, and the excellent solubility make our vanadium compounds highly interesting for applications as building blocks in macromolecular chemistry as well as redox labels in biochemistry.

When Al2(OtBu)6 is treated with ethanol Al9O3(OEt)21 (1) is obtained, which is a missing link in the series of polynuclear aluminium alkoxides. Alcoholysis of Al2(OtBu)6 in isopropanol yields the well-known homoleptic compound Al4(OiPr)12 (2). As recently published, similar reactions with Fe2(OtBu)6 gave different structures. However, there are recurring structural patterns from alkoxide chemistry found. For a deeper understanding of this hardly predictable chemistry, compounds have to be correlated by such common structural motifs. We briefly report the syntheses of 1 and 2 and the crystal structure of 1. In addition, we provide an improved synthetic procedure for the preparation of the precursor Al2(OtBu)6. The structure of the new compound 1 is comprehensively compared to related structures from literature.

The deep blue, paramagnetic Cs2[TcII(NO)F5] is formed during reactions of pertechnetate, acetohydroxamic acid, and CsF in aqueous HF. A reaction of Cs2[Tc(NO)F5] with BF3·MeOH in acetonitrile gives yellow blocks of the fluorido-bridged dimer [{TcI(NO)(CH3CN)4}2F](BF4)3. The compound is stable as solid and in acetonitrile solutions. The complex cation contains a bent μ-F– ligand and two linear nitrosyl groups.

Wir berichten uber die Synthesen, Kristallstrukturen und physikalischen Eigenschaften von [HFe19O14(OEt)30] und [{Fe11(OEt)24}∞]. Das oktaederformige Molekul [HFe19O14(OEt)30] kann als dreidimensionaler Ausschnitt aus dem Natriumchloridgitter aufgefasst werden, wobei das zentrale Eisenion von sechs μ6-Oxo-Gruppen koordiniert ist. [{Fe11(OEt)24}∞] ist ein gemischtvalentes Koordinationspolymer, in dem die FeIII-Ionen ein dreidimensionales (10,3)-b-Netz bilden. Die Anordnung der FeIII-Ionen ist mit der von Siliciumionen in α-ThSi2 vergleichbar. Die beschriebenen Strukturen zeigen eine Schnittstelle zwischen Molekul- und Festkorperchemie auf.

The syntheses and crystal structures of [MnCl3(H2O)(THF)2]·2THF (I), [MnCl4(THF)2][H(THF)2] (II), and [MnCl3(THF)3] (III) are reported. This study shows that former assumptions about the preparation of anhydrous MnCl3 and its etherates, published in the 1960s and earlier, have to be questioned. Instead of the conventional manganese sources, MnF3 was successfully utilized as starting material in THF to give water-free MnCl3 etherates. These findings are vital for further reactions where reactive but anhydrous MnCl3 derivatives are needed.

Novel synthetic routes to hexafluoridotechnetate(IV) are reported, and for the first time the single-crystal X-ray structures of several M2[TcF6] salts (M = Na, K, Rb, Cs, NH4, and NMe4) were determined. The ammonium and the alkaline metal salts crystallize in the trigonal space group P3m, while the NMe4(+) salt belongs to the space group R3. [TcF6](2-) salts are widely stable in aqueous solution. In alkaline media, however, a slow hydrolysis is observed, and the first hydrolysis product, the dimeric, oxido-bridged complex [F5Tc-O-TcF5](4-), could be studied structurally.

We report a study on the structure directing effects of functional groups and counterions. The aim was to find a facile and high yielding synthetic procedure to obtain polyoxometalate (POM) building blocks for post-functionalisation. Therefore, solvothermal reactions of VOSO

We report a study on the structure directing effects of functional groups and counterions. The aim was to find a facile and high yielding synthetic procedure to obtain polyoxometalate (POM) building blocks for post- functionalisation. Therefore, solvothermal reactions of VOSO4 with various tris(hydroxymethyl)methane derivatives in alkaline methanolic solutions were investigated. In doing so, new POM fragments were isolated and characterised. The binding modes of the functionalised tripodal alkoxides turned out to be surprisingly different.

We have studied the properties of a series of solid hydrated organic porous networks with pore diameters ranging from approximately 0.4 to 0.9 nm using the attenuated total reflection infrared (ATR-IR) technique. These subnanometer organic pores are composed of water and of organic racemic bicyclic monomers containing carboxylic, alcoholic, ether functions and different appendices. In particular, the doubly hydrated hydroxyl acids 1 2H2O and 2 2H 2O form cylindrical pores in which half of the water molecules are part of the walls and the other half are located inside the pores. In a first step, by a comparison of the spectra of a family of related compounds, the COOH, COH as well as the wall and pore water stretches were assigned. The COOH bands are broad and red-shifted as compared to carboxylic acid dimers, and exhibit a substructure assigned to Fermi resonances. The OH stretches fulfill well Novak's correlation with the corresponding crystallographic O...O distances. In a second step, we have followed the deuteration of the different functional groups of solid 2 2H2O by ATR-IR by heavy water vapor. Surprisingly, we observe that the rates of deuteration are the same for all functional groups although exhibiting biexponential time dependence, in contrast to the liquid state where COOH groups exchange protons with water much faster than with alcohols. This result is rationalized in terms of slowly diffusing lattice defects resembling a local liquid or glass in the subnano scale in which the different exchange reactions take place. The nonexponential deuteration is explained in terms of a faster deuteration of crystal surface layers. © 2011 American Chemical Society., The financial support from the Spanish Ministry of Science and Technology (MST/FEDER, project CTQ2007-61024/BQU), of the Deutsche Forschungsgemeinschaft, Bonn, Germany and of the Fonds der Chemischen Industrie, Frankfurt, is gratefully acknowledged . N.P.H. thanks the Ramón Areces Foundation for a postdoctoral grant.

Two tetraorganoditelluroxane diiodides (R2Te)2OI2 (3, R = p-MeOC6H4; 5, R = Me) were prepared by the reaction of (p-MeOC6H4)2TeI2 (1) and (p-MeOC6H4)2TeO (2) and the base hydrolysis of Me2TeI2 (4), respectively. The base hydrolysis of C4H8TeI2 (8) afforded the tritelluroxane diiodide (C4H8Te)3O2I2 (9). The reaction of Me2TeI2 (4) and Me2Te(OH)2 (6) in a ratio of 1:3 produced the coordination polymer of the composition 2 (Me2Te)2O(I)OH · H2O (7). An attempt at preparing an adduct of 3 with iodine failed but provided co-crystals of (p-MeOC6H4)2TeI2 · 1 2 I2 (1a). The supramolecular structures of 1a, 3, 5, 7 and 9 are dominated by structurally directing secondary Te⋯I interactions.

International audience; The syntheses, crystal structures, and physical properties of [HFe19O14(OEt)30] and {Fe11(OEt)24}1 are reported. [HFe19O14(OEt)30] has an octahedral shape. Its core with a central Fe metal ion surrounded by six m6-oxo ligands is arranged in the rock salt structure. {Fe11(OEt)24}1 is a mixedvalencecoordination polymer in which FeIII metal ions form three 3D interpenetrating (10,3)-b nets. The arrangement of the FeIII ions can also be compared to that of Si ions in a-ThSi2. Thus, the described structures are at the interface between molecular and solid-state chemistry.

IR and Raman spectra of two fluorofullerenes, C60F48 and C60F36, are thoroughly studied. Assignment of the experimental spectra is provided on the basis of density functional theory (DFT) computations. Perfect correspondence between experimental and computed spectra enabled us to confirm that the major isomer of C60F48 has D3 symmetry. It was found that as-synthesized samples of C60F36 consist mainly of C3 and C1 isomers in ca. 2:1 ratio and 2-3% of T-symmetric structures. Extensive AM1 and DFT computations have shown that all three structures are the most stable isomers of C60F36. Previous structural assignment of the C3 isomer (Gakh, A. A.; Tuinman, A. A. Tetrahedron Lett. 2001, 42, 7137-7139) was confirmed by the vibrational data.

Reaction of C70 with ten equivalents of silver(I) trifluoroacetate at 320-340 degrees C followed by fractional sublimation at 420-540 degrees C and HPLC processing led to the isolation of a single abundant isomer of C70(CF3)n for n = 2, 4, 6, and 10, and two abundant isomers of C70(CF3)8. These six compounds were characterized by using matrix-assisted laser desorption ionization (MALDI) mass spectrometry, 2D-COSY and/or 1D 19F NMR spectroscopy, and quantum-chemical calculations at the density functional theory (DFT) level. Some were also characterized by Raman spectroscopy. The addition patterns for the isolated compounds were unambiguously found to be C1-7,24-C70(CF3)2, C1-7,24,44,47-C70(CF3)4, C2-1,4,11,19,31,41-C70(CF3)6, Cs-1,4,11,19,31,41,51,64-C70(CF3)8, C2-1,4,11,19,31,41,51,60-C70(CF3)8, and C1-1,4,10,19,25,41,49,60,66,69-C70(CF3)10 (IUPAC numbering). Except for the last compound, which is identical to the recently reported, crystallographically characterized C70(CF3)10 derivative prepared by a different synthetic route, these compounds have not previously been shown to have the indicated addition patterns. The largest relative yield under an optimized set of reaction conditions was for the Cs isomer of C70(CF3)8 (ca. 30 mol % of the sublimed mixture of products based on HPLC integration). The results demonstrate that thermally stable C70(CF3)n isomers tend to have their CF3 groups arranged on isolated para-C6(CF3)2 hexagons and/or on a ribbon of edge-sharing meta- and/or para-C6(CF3)2 hexagons. For Cs- and C2-C70(CF3)8 and for C2-C70(CF3)6, the ribbons straddle the C70 equatorial belt; for C1-C70(CF3)4, the para-meta-para ribbon includes three polar hexagons; for C1-7,24-C70(CF3)2, the para-C6(CF3)2 hexagon includes one of the carbon atoms on a C70 polar pentagon. The 10.3-16.2 Hz 7JF,F NMR coupling constants for the end-of-ribbon CF3 groups, which are always para to their nearest-neighbor CF3 group, are consistent with through-space Fermi-contact interactions between the fluorine atoms of proximate, rapidly rotating CF3 groups.

Alcoholysis of [Fe2(OtBu)6] as a Simple Route to New Iron(III)-Alkoxo Compounds: Synthesis and Crystal Structures of [Fe2(OtAmyl)6], [Fe5OCl(OiPr)12], [Fe5O(OiPr)13], [Fe5O(OiBu)13], [Fe5O(OCH2CF3)13], [Fe5O(OnPr)13], and [Fe9O3(OnPr)21] · nPrOH New alkoxo-iron compounds can be synthesized easily by alcoholysis of [Fe2(OtBu)6] (1). Due to different bulkyness of the alcohols used, three different structure types are formed: [Fe2(OR)6], [Fe5O(OR)13] and [Fe9O3(OR)21] · ROH. We report synthesis and crystal structures of the compounds [Fe5OCl(OiPr)12] (2), [Fe2(OtAmyl)6] (3), [Fe5O(OiPr)13] (4), [Fe5O(OiBu)13] (5), [Fe5O(OCH2CF3)13] (6), [Fe9O3(OnPr)21] · nPrOH (7) and [Fe5O(OnPr)13] (8). Crystallographic Data:2, tetragonal, P 4/n, a = 16.070(5) A, c = 9.831(5) A, V = 2539(2) A3, Z = 2, dc = 1.360 gcm−3, R1 = 0.0636; 3, monoclinic, P 21/c, a = 10.591(5) A, b = 10.654(4) A, c = 16.740(7) A, β = 104.87(2)°, V = 1826(2) A3, Z = 2, dc = 1.154 gcm−3, R1 = 0.0756; 4, triclinic, , a = 20.640(3) A, b = 21.383(3) A, c = 21.537(3) A, α = 82.37(1)°, β = 73.15(1)°, γ = 61.75(1)°, V = 8013(2) A3, Z = 6, dc = 1.322 gcm−3, R1 = 0.0412; 5, tetragonal, P 4cc, a = 13.612(5) A, c = 36.853(5) A, V = 6828(4) A3, Z = 4, dc = 1.079 gcm−3, R1 = 0.0609; 6, triclinic, , a = 12.039(2) A, b = 12.673(3) A, c = 19.600(4) A, α = 93.60(1)°, β = 97.02(1)°, γ = 117.83(1)°, V = 2600(2) A3, Z = 2, dc = 2.022 gcm−3, R1 = 0.0585; 7, triclinic, , a = 12.989(3) A, b = 16.750(4) A, c = 21.644(5) A, α = 84.69(1)°, β = 86.20(1)°, γ = 77.68(1)°, V = 4576(2) A3, Z = 2, dc = 1.344 gcm−3, R1 = 0.0778; 8, triclinic, , a = 12.597(5) A, b = 12.764(5) A, c = 16.727(7) A, α = 91.94(1)°, β = 95.61(1)°, γ = 93.24(2)°, V = 2670(2) A3, Z = 2, dc = 1.323 gcm−3, R1 = 0.0594.

The hexanuclear methoxo-oxovanadium cluster V6O7(OCH3)12 (1) is investigated by electrospray ionization in methanol solution. Collision experiments unravel the fragmentation schemes of the molecular ions 1+ and 1− as well as the H+, Na+, and Cs+ adducts of 1. In general, fragmentation of the hexanuclear cluster ions commences with sequential expulsions of two OV(OCH3)3 units to yield the corresponding V4 clusters. However, when an active proton is present in the cluster ion, e.g., in the protonated molecule [ 1 + H ]+, loss of methanol precedes degradation to V4 clusters. In addition, the experiments suggest that electrospray ionization provides as an alternative method for the generation of metal oxide cluster ions VmOn+/− (m=1–4, n=0–11).

Durch Reaktion von Eisen(III)-chlorid in Diethylether mit Natrium-tert-butylat konnte das homoleptische dimere tert-Butoxid [Fe2(OtBu)6] (1) hergestellt werden. Die Chloro-Derivate [Fe2Cl2(OtBu)4] (2) und [Fe2Cl4(OtBu)2] (3) wurden durch Liganden-Austausch zwischen 1 und Eisen(III)-chlorid synthetisiert. In 1, 2 und 3 liegen jeweils zwei kantenverknupfte Tetraeder mit zwei tert-Butoxo-Gruppen als Bruckenliganden vor. Eine entscheidende Rolle fur die Synthese von 1, 2 und 3 spielt das verwendete Losungsmittel Diethylether, wobei sich primar das Dietherat des Eisen(III)-chlorids FeCl3(OEt2)2 (4) bildet. Durch Reaktion von Eisen(III)-chlorid mit Tetrabutylammoniummethoxid in Methanol konnte daruberhinaus ein Chloro-Methoxo-Oxo-Hexaeisen-Cluster [N(nBu)4]2[Fe6OCl6(OMe)12] (5) mit Tetrabutylammonium als Kation synthetisiert und strukturell charakterisiert werden. Alkoxo Compounds of Iron(III): Syntheses and Characterization of [Fe2(OtBu)6], [Fe2Cl2(OtBu)4], [Fe2Cl4(OtBu)2] and [N(nBu)4]2[Fe6OCl6(OMe)12] The reaction of iron(III)chloride in diethylether with sodium tert-butylat yielded the homoleptic dimeric tert--butoxide Fe2(OtBu)6 (1). The chloro-derivatives [Fe2Cl2(OtBu)4] (2), and [Fe2Cl4(OtBu)2] (3) could be synthesized by ligand exchange between 1 and iron(III)chloride. Each of the molecules 1, 2, and 3 consists of two edge-sharing tetrahedrons, with two tert-butoxo-groups as μ2-bridging ligands. For the synthesis of the alkoxides 1, 2, and 3 diethylether plays an important role. In the first step the dietherate of iron(III)chloride FeCl3(OEt2)2 (4) is formed. The reaction of iron(III)chloride with tetrabutylammonium methoxide in methanol results in the formation of a tetrabutylammonium methoxo-chloro-oxo-hexairon cluster [N(nBu)4]2[Fe6OCl6(OMe)12] (5). Crystal structure data:1, triclinic, P1¯, a = 9.882(2) A, b = 10.523(2) A, c = 15.972(3) A, α = 73.986(4)°, β = 88.713(4)°, γ = 87.145(4)°, V = 1594.4(5) A3, Z = 2, dc = 1.146 gcm—1, R1 = 0.044; 2, monoclinic, P21/n, a = 11.134(2) A, b = 10.141(2) A, c = 12.152(2) A und β = 114.157(3)°, V = 1251.8(4) A3, Z = 2, dc = 1.377 gcm—1, R1 = 0.0581; 3, monoclinic, P21/n, a = 6.527(2) A, b = 11.744(2) A, c = 10.623(2), β = 96.644(3)°, V = 808.8(2) A3, Z = 2, dc = 1.641 gcm—1, R1 = 0.0174; 4, orthorhombic, Iba2, a = 23.266(5) A, b = 9.541(2) A, c = 12.867(3) A, V = 2856(2) A3, Z = 8, dc = 1.444 gcm—1, R1 = 0.0208; 5, trigonal, P31, a = 13.945(2) A, c = 30.011(6) A, V = 5054(2) A3, Z = 6, dc = 1.401 gcm—1; Rc = 0.0494.

Durch Umsetzung von ortho-Vanadinsauremethylester [VO(OMe)3] mit Quadratsaure und Kalium- bzw. Caesiumhydroxid konnten unter Solvothermalbedingungen die Verbindungen K4[VIV12O12(OCH3)16(C4O4)6] (2) und Cs10[VIV24O24(OCH3)32(C4O4)12][VIV8O8(OCH3)16(C2O4)] (3) synthetisiert werden. Mit Tetra-n-butyl- bzw. Tetra-n-ethylammoniumfluorid erhalt man [N(nBu)4]2[VIV8O8(OCH3)16(VIVOF4)] (4) und [N(Et)4]2[VIV8O8(OCH3)16(VIVOF4)] (5). In den Verbindungen 2 und 3 sind an den Ecken eines Tetraeders bzw. Wurfels sitzende {(VO)3(OMe)4}-Gruppen entlang der Tetraeder- bzw. Wurfelkanten uber sechs bzw. zwolf Quadratatogruppen miteinander verknupft. Die achtkernigen Anionen in den Verbindungen 3, 4 und 5 kann man sich aus oligomeren, kettenformigen Fragmenten des Vanadinsauremethylesters, die sich um die Anionen C2O42— oder VOF4— zum Ring schliessen, aufgebaut denken. Kristalldaten: 2, tetragonal, P43, a = 18, 166(3)A, c = 29, 165(7)A, V = 9625(3)A3, Z = 4, dc = 1, 469 gcm—3; 3, orthorhombisch, Pbca, a = 29, 493(5)A, b = 25, 564(4)A, c = 31, 076A, V = 23430(6)A3, Z = 4, dc = 1, 892 gcm—3; 4, monoklin, P21/n, a = 9, 528(1)A, b = 23, 021(2)A, c = 19, 303(2)A, β = 92, 570(2)°, V = 4229, 8(5)A3, Z = 2, dc = 1, 391 gcm—3; 5, monoklin, P21/n, a = 16, 451(2)A, b = 8, 806(1)A, c = 23, 812(1)A, β = 102, 423(2)°, V = 3368, 7(6)A3, Z = 2, dc = 1, 534 gcm—3. >From Small Fragments to New Poly-alkoxo-oxo-metalate Derivatives: Syntheses and Crystal Structures of K4[VIV12O12(OCH3)16(C4O4)6], Cs10[VIV24O24(OCH3)32(C4O4)12][VIV8O8(OCH3)16(C2O4)], and M2[VIV8O8(OCH3)16(VIVOF4)] (M = [N(nBu)4] or [NEt4]) By solvothermal reaction of ortho-vanadicacid ester [VO(OMe)3] with squaric acid and potassium or caesium hydroxide the compounds K4[VIV12O12(OCH3)16(C4O4)6] (2) and Cs10[VIV24O24(OCH3)32(C4O4)12][VIV8O8(OCH3)16(C2O4)] (3) could be syntesized. With tetra-n-butyl- or tetra-n-ethylammonium fluoride [N(nBu)4]2[VIV8O8(OCH3)16(VIVOF4)] (4) and [N(Et)4]2[VIV8O8(OCH3)16(VIVOF4)] (5) could be isolated. In 2 and 3 the corners of a tetrahedron or cube resp. are occupied by {(VO)3(OMe)4} groups and connected along the edges of the tetrahedron resp. cube by six or twelve resp. squarato-groups. The octanuclear anions in the compounds 3, 4, and 5 are assumedly built up by fragments of the ortho-vanadicacid ester [VO(OMe)3]. Around the anions C2O42— or VOF4— these oligormeric chains are closed to a ring . Crystal data: 2, tetragonal, P43, a = 18.166(3)A, c = 29.165(7)A, V = 9625(3)A3, Z = 4, dc = 1.469 gcm—3; 3, orthorhombic, Pbca, a = 29.493(5)A, b = 25.564(4)A, c = 31.076A, V = 23430(6)A3, Z = 4, dc = 1.892 gcm—3; 4, monoclinic, P21/n, a = 9.528(1)A, b = 23.021(2)A, c = 19.303(2)A, β = 92.570(2)°, V = 4229.8(5)A3, Z = 2, dc = 1.391 gcm—3; 5, monoclinic, P21/n, a = 16.451(2)A, b = 8.806(1)A, c = 23.812(1)A, β = 102.423(2)°, V = 3368.7(6)A3, Z = 2, dc = 1.534 gcm—3.

A mixture of [Tc(NO)F5](2-) and [Tc(NO)(NH3)4F](+) is formed during the reaction of pertechnetate with acetohydroxamic acid (Haha) in aqueous HF. The blue pentafluoridonitrosyltechnetate(II) has been isolated in crystalline form as potassium and rubidium salts, while the orange-red ammine complex crystallizes as bifluoride or PF6(-) salts. Reactions of [Tc(NO)F5](2-) salts with HCl give the corresponding [Tc(NO)Cl4/5](-/2-) complexes, while reflux in neat pyridine (py) results in the formation of the technetium(I) cation [Tc(NO)(py)4F](+), which can be crystallized as hexafluoridophosphate. The same compound can be synthesized directly from pertechnetate, Haha, HF, and py or by a ligand-exchange procedure starting from [Tc(NO)(NH3)4F](HF2). The technetium(I) cation [Tc(NO)(NH3)4F](+) can be oxidized electrochemically or by the reaction with Ce(SO4)2 to give the corresponding Tc(II) compound [Tc(NO)(NH3)4F](2+). The fluorido ligand in [Tc(NO)(NH3)4F](+) can be replaced by CF3COO(-), leaving the "[Tc(NO)(NH3)4](2+) core" untouched. The experimental results are confirmed by density functional theory calculations on [Tc(NO)F5](2-), [Tc(NO)(py)4F](+), [Tc(NO)(NH3)4F](+), and [Tc(NO)(NH3)4F](2+).

Polydentate bridging ligands can be used to link small polyoxo-alkoxo-metalate units to form supramolecular clusters. In the title compound, twelve μ4 -bridging squarato groups connect eight trinuclear methoxo-oxo-vanadate units to form a tetradodecanuclear cubic framework, in whose cavity six n-butyl groups of the tetra-n-butylammonium cations are anchored.

Polydentate bridging ligands can be used to link small polyoxo-alkoxo-metalate units to form supramolecular clusters. In the title compound, twelve μ

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