The reaction of arsenic pentafluoride with graphite fluorosulfate

The reaction of graphite fluorosulfate with an excess of arsenic(V) fluoride produces the new intercalation compound C₁₄⁺ [AsF₅(SO₃F)]^?. Identification as a first stage compound rests on the observed interlayer separation of 7.92 Å and the position of ν_E2g at 1636 cm^?1 in the Raman spectrum. Evidence for [AsF₅(SO₃F)]^? as intercalant is based on ¹⁹F NMR spectra of the solid material. C¹⁴⁺[AsF₅(SO₃F)]^? is found to exhibit high electrical conductivities in the basal plane.     

Über das Donor‐Verhalten von Bis(pyrazolyl)‐Schwefel‐Derivaten

The Donor Properties of Bis(pyrazolyl)‐Sulfur Derivatives From the reactions of bis(pyrazolyl)sulfane S(pz)₂ ( 1 ) with the fluoro Lewis acids BF₃ and AsF₅ in liquid SO₂ the 1:2‐adducts S(pz·BF₃)₂ ( 2 ) and S(pz·AsF₅)₂ ( 3 ) are obtained. 1 reacts with [Co(SO₂)₄(FAsF₅)₂] to give the doubly bridged FAsF₄F dimeric complex [Co{S(pz)₂}(FAsF₅)(SO₂)(μ‐FAsF₄F)]₂ ( 5 ). From F₂S(pz)₂ and [Ni(SO₂)₆](AsF₆)₂, the fluorocubane [Ni₄F₄{S(pz)₂}₄(μ‐FAsF₄F)₂](AsF₆)₂·4SO₂ ( 8 ) is isolated. The X‐ray structures of the compounds 2 , 3 , 5 and 8 are reported.     

The bromine catalysed oxidation of arsenic trifluoride by antimony pentafluoride

Antimony pentafluoride dissolves in excess arsenic trifluoride presumably with the formation of AsF₃·SbF₅ [1,2] and possibly (AsF₃)_nSbF₅ n = 2, [3], 3, [4], in equilibrium with one another and the solvent. However, O. Ruff [5] found in 1906 that in the presence of bromine, antimony pentafluoride oxidises arsenic trifluoride to arsenic pentafluoride with formation of a solid he suggested was SbBrF₄. In the course of our work we investigated this reaction and found that trace quantities of bromine (<0.1 mole per cent) catalyse the formation of arsenic pentafluoride and SbF₃·SbF₅ [6], according to equation (1).AsF₃ + 2SbF₅ = AsF₅ + SbF₃·SbF₅ (1)Reaction (2) is endothermic to the extent of ca. 33 Kcals mole^?1 [7–9], but reaction (1) occurs spontaneously in presence of bromine, being more favourable than reaction (2) by the heat of reaction (3).AsF₃ + SbF₅ = AsF₅ + SbF₃ (2)SbF₃ + SbF₅ = SbF₃·SbF₅ (3)     

The synthesis and vibrational spectra of the antimony(V)fluoride-fluorosulfates SbF3(SO3F)2, SbF4(SO3F) and Sb2F9(SO3F)

The synthesis of the title compounds by a variety of routes is described. These routes involve the oxidation of antimony(III)fluoride by bis(fluorosulfuryl)peroxide and the use of non-statistical ligand redistribution reactions. Complex formation with ClO₂SO₃F leads to ClO₂[SbF_n(SO₃F)_6-n], with n=3 or 4. Polarized Raman data and low temperature infrared data are reported. All antimony(V)fluoride-fluorosulfates are found to have fluorosulfate bridges with SbF₃(SO₃F)₂ and SbF₄(SO₃F) being polymers. Ionic formulations for the ClO⁺₂ complexes are again based on vibrational spectra.     

Dioxouranium(VI) and oxouranium(IV) fluorosulphates and double fluorosulphates of uranium(IV)

UO₂(SO₃F)₂, UO(SO₃F)₂, U(SO₃F)₄ and MU(SO₃F)₆, MMg, Zn have been prepared by reacting UO₂(O₂CCH₃)₂, U(O₂CCH₃)₄, U(O₂CCF₃)₄ and MU(O₂CCH₃)₆ with HSO₃F. The analysis of i.r. spectral data of UO₂(SO₃F)₂, UO(SO₃F)₂ and MU(SO₃F)₆ shows the presence of only one type of SO₃F group with reduced symmetry C_s. In U(SO₃F)₄, two SO₃F groups are bidentate, while the other two are monodentate. A sharp band at 925 cm^?1 in UO₂(SO₃F)₂ is diagnostic of UO₂²⁺. The diffuse reflectance spectra of UO(SO₃F)₂, U(SO₃F)₄ and MU(SO₃F)₆ reveal hexacoordination of U(IV), while the magnetic moments of these compounds support the existence of U(IV). UO₂(SO₃F)₂ and UO(SO₃F)₂ decompose thermally in a single step with the evolution of SO₂F₂ and formation of their respective sulphates.     

The Simultaneous Oxidation of Tellurium and Transition Metals by AsF5 – Syntheses and Crystal Structures of [M(SO2)6](Te6)[AsF6]6 (M = Ni,Zn) and [Cd(SO2)2][AsF6]2

The reactions of elemental nickel and tellurium and of ZnTe with excess AsF₅ in liquid SO₂ yield [M(SO₂)₆](Te₆)[AsF₆]₆ (M = Ni, Zn) as orange crystals. The crystal structure determinations (triclinic, , M = Ni: a = 1632.59(2), b = 1795.06(1), c = 1822.97(2) pm, α = 119.11(4), β = 90.78(4), γ = 106.28(4)°, V = 4408.24(8)·10⁶pm³, Z = 4) show the two compounds to be isotypic. The structures are made up of discrete [M(SO₂)₆]²⁺ complexes, Te₆⁴⁺ clusters and octahedral [AsF₆]^? ions. In the [M(SO₂)₆]²⁺ complexes the metal ions are surrounded octahedrally by six SO₂ molecules bound via the O atoms. The Te₆⁴⁺ polycations are of trigonal prismatic shape with short Te–Te bonds within the triangular faces (270 pm) and long Te–Te bonds along the edges parallel to the pseudo C₃ axes of the prisms (312 pm). The arrangement of the ions is related to the Li₃Bi structure type. [M(SO₂)₆]²⁺ complexes and Te₆⁴⁺ polycations together form a distorted cubic closest packing with all tetrahedral and octahedral interstices filled by [AsF₆]^? ions. The analogous reaction starting from CdTe did not yield a compound containing simultaneously [Cd(SO₂)_n]²⁺ complexes and tellurium polycations but instead Te₆[AsF₆]₄ · 2 SO₂ besides [Cd(SO₂)₂][AsF₆]₂ were obtained. It crystallizes isotypically to [Mn(SO₂)₂][AsF₆]₂ (Mews, Zemva, 2001) (orthorhombic, Fdd2, a = 1534.96(3), b = 1812.89(3), c = 892.28(3) pm, V = 2483·10⁶ pm³, Z = 4).     

Chelat-Sandwichkomplexe des Tripod-Liganden Tris(diethoxyphosphoryl)phosphan mit zweiwertigen Kationen von Mangan,Eisen, Cobalt und Nickel

Chelate-like Sandwich Complexes of the Tripod Ligand Tris(diethoxyphosphoryl)phosphane with Bivalent Cations of Manganese, Iron, Cobalt, and Nickel P[P(O)(OR)₂]₃ ( 1 , R ? C₂H₅) and the transition metal hexafluoroarsenates M(SO₂)₂(AsF₆)₂ (M ? Mn, Fe, Co, Ni) form the remarkably stable 2:1 complexes M{P[P(O)(OR)₂]₃}₂ (AsF₆)₂ 2–5 in liquid SO₂. Two tripod chelate ligands are arranged like a sandwich around the metal cation. Spectroscopic and magnetic properties of the compounds are discussed.     

Zum Reaktionsverhalten der Tris(dialkylthiophosphinyl)phosphane – Die Kristallstruktur von [Ag{O[P(S)Me2]2}2] [AsF6]

Reactivity of Tris(dialkylthiophosphinyl)phosphines – Crystal Structure of [Ag{O[P(S)Me₂]₂}₂][AsF₆] In contrast to tris(dialkylphosphoryl)phosphines the reaction of tris(dimethylthiophosphinyl)phosphine with transition metal hexafluoroarsenates of the type [M(SO₂)_m [AsF₆]_n (M = Ag, m = 0, n = 1; M = Fe, Cd, m = n = 2) forms no molecular 2 : 1-complexes but polymeric products. The silver polymer is transformed into [Ag{O[P(S)Me₂]₂}₂][AsF₆], which is also formed by the reaction of Ag[AsF₆] with O[P(S)Me₂]₂. It crystallizes in the space group P1 with a = 862.5(2), b = 1 241.4(2), c = 1 254.0(3)pm, α = 80.34(1), β = 101.99(6), γ= 73.75(1)° (at 20°C) and Z = 2. The central silver atom is surrounded by four sulphur atoms in a slighly distorted tetrahedron. The average (Ag? S) and (P? S) bond lengthes are 259.4(2) pm and 194.9(2)pm, respectively.     

The ESR spectrum of arsenic tetrafluoride

The ESR spectrum of AsF₄, generated by γ-radiolysis of a solid solution of AsF₃ in SF₆, is reported. The ⁷⁵As hyperfine interaction is 1576 G, and the two kinds of ¹⁹F nuclei have interactions of 49 G (equatorial) and 238 G (apical). These data are compared with those from the well-known PF₄ radical.     

Mixed halide dialkyldithiophosphate derivatives of arsenic(III) and antimony(III)

Mixed chloride dialkyldithiophosphates of arsenic(III) and antimony(III), [(RO)₂PSS]_nMCl_3?n (M = As, Sb; n = 1, 2; R = C₂H₅, n-C₃H₇, i-C₃H₇ and i-C₄H₉) have been synthesized for the first time by the reac metal chlorides with sodium dialkyldithiophosphates or alternatively by co-disproportionation reactions of metal chlorides with metal tris(dialkyldithiophosphates) in different stoichiometric ratios. Mixed halide dialkyl-dithiophosphates of antimony(III) have also been prepared by the cleavage reactions of antimony tris(diisopropyldithiophosphate) with bromine or iodine. Hydrolysis reactions of a few of these compounds have also been studied. The new compounds have been characterized by elemental analyses, molecular weight determinations (cryoscopic) as well as IR and NMR (¹H, ³¹P) data; chelated structures with bidentate dialkyldithiophosphate groups are proposed.     

Über eine einfache Darstellungsweise von Arsentrifluorid und eine Molekülverbindung mit Schwefeltrioxyd

Zusammenfassung AsF₃ und SO₃ treten zu einer unzersetzt destillierbaren Molekülverbindung 2 AsF₃·3 SO₃ zusammen. Diese entsteht nicht bei der Umsetzung von HSO₃F mit As₂O₃, die Reaktion läßt sich aber vorteilhaft zur Herstellung von AsF₃ in einer Glasapparatur verwenden.     

Alkaline earth metal poly(hydrogen fluorides) hexafluoroarsenates(V) and hexafluorophosphate(V): M2(H2F3)(HF2)2(AF6) (M = Ca, A = As; M = Sr, A = As, P)

New compounds of the type M₂(H₂F₃)(HF₂)₂(AF₆) with M = Ca, A = As and M = Sr, A = As, P) were isolated. Ca₂(H₂F₃)(HF₂)₂(AsF₆) was prepared from Ca(AsF₆)₂ with repeated additions of neutral anhydrous hydrogen fluoride (aHF). It crystallizes in a space group P4₃22 with a = 714.67(10) pm, c = 1754.8(3) pm, V = 0.8963(2) nm³ and Z = 4. Sr₂(H₂F₃)(HF₂)₂(AsF₆) was prepared at room temperature by dissolving SrF₂ in aHF acidified with AsF₅ in mole ratio SrF₂:AsF₅ = 2:1. It crystallizes in a space group P4₃22 with a = 746.00(12) pm, c = 1805.1(5) pm, V = 1.0046(4) nm³ and Z = 4. Sr₂(H₂F₃)(HF₂)₂(PF₆) was prepared from Sr(XeF₂)_n(PF₆)₂ in neutral aHF. It crystallizes in a space group P4₁22 with a = 737.0(3) pm, c = 1793.7(14) pm, V = 0.9744(9) nm³ and Z = 4. The compounds M₂(H₂F₃)(HF₂)₂(AF₆) gradually lose HF at room temperature in a dynamic vacuum or during being powdered for recording IR spectra or X-ray powder ray diffraction patterns. All compounds are isotypical with coordination of nine fluorine atoms around a metal center forming a distorted Archimedian antiprism with one face capped. This is the first example of the compounds in which H₂F₃⁻ and HF₂⁻ anions simultaneously bridge metal centers forming close packed three-dimensional network of polymeric compounds with low solubility in aHF. The HF₂⁻ anions are asymmetric with usual F?F distances of 227.3-228.5 pm. Vibrational frequency (ν₁) of HF₂⁻ is close to that in NaHF₂. The anion H₂F₃⁻ exhibits unusually small F?F?F angle of 95.1°-97.6° most probably as a consequence of close packed structure.     

Barium,Potassium, and Tris(ethane‐1,2‐diamine)nickel(II) Fluoroalkanedisulfonates and the X‐ray Crystal Structures of K2(O3S)2CHF,K2(O3S)2CF2, K2(O3S)2(CF2)3 · H2O,and [Nien3][(O3S)2(CF2)n] (n = 1, 3)

The barium perfluoroalkanedisulfonates Ba(O₃S)₂(CF₂)_n (n = 1, 3–5) and the new potassium fluoroalkanedisulfonates K₂(O₃S)₂CHF, K₂(O₃S)₂CF₂, and K₂(O₃S)₂(CF₂)₅ have been prepared by reaction of (CF₂)_n(SO₂F)₂ (n = 1, 3–5) or CHF(SO₂F)₂ with CaO (or Ca(OH)₂) and M(OH)_x (M = Ba, x = 2; M = K, x = 1) or with Ba(OH)₂ alone (n = 1) in water. In each of the crystal structures of K₂(O₃S)₂CHF and K₂(O₃S)₂CF₂, there is an eight‐coordinate and a six‐coordinate potassium ion, whilst in K₂(O₃S)₂(CF₂)₃H₂O, two different eight‐coordinate potassium ions are linked by a bridging water molecule. One potassium has additionally six sulfonate oxygen and one fluorine donor atoms, and the other, five sulfonate oxygens and two fluorine donor atoms. The preparation of highly crystalline [Nien₃][(O₃S)(CF₂)_n] (en = ethane‐1,2‐diamine; n = 1, 3–5) and the X‐ray crystal structures for n = 1 or 3 provide evidence for the value of perfluoroalkanedisulfonate ions as counter ions for the crystallization of cationic complexes.     

The Protonation of Acetamide and Thioacetamide in Super­acidic Solutions: Crystal Structures of [H3CC(OH)NH2]+AsF6– and [H3CC(SH)NH2]+AsF6–

Acetamide and thioacetamide react with the superacid solutions HF/MF₅ (M = As, Sb) under formation of the corresponding salts [H₃CC(OH)NH₂]⁺MF₆^– and [H₃CC(SH)NH₂]⁺MF₆^– (M = As, Sb), respectively. The reaction of DF/AsF₅ with acetamide and thioacetamide lead to the corresponding deuterated salts [H₃CC(OD)ND₂]⁺AsF₆^– and [H₃CC(SD)ND₂]⁺AsF₆^–, respectively_. The salts are characterized by vibrational and NMR spectroscopy, and in the case of [H₃CC(OH)NH₂]⁺AsF₆^– and [H₃CC(SH)NH₂]⁺AsF₆^– also by single‐crystal X‐ray analyses. The [H₃CC(OH)NH₂]⁺AsF₆^– ( 1 ) salt crystallizes in the triclinic space group P$\bar{1}$ with two formula units per unit cell, and the [H₃CC(SH)NH₂]⁺AsF₆^– ( 2 ) salt crystallizes in the monoclinic space group P2₁/c with four formula units per unit cell. In both crystal structures three‐dimensional networks are observed which are formed by intra‐ and intermolecular N–H ··· F and O–H ··· F or S–H ··· F hydrogen bonds, respectively. For the vibrational analyses, quantum chemically calculated spectra of the cations [H₃CC(OH)NH₂ · 3HF]⁺ and [H₃CC(SH)NH₂ · 2HF]⁺ are considered.     

Preconcentration of arsenic(V) as molybdoarsenic heteropoly acid by dynamic sorption

The sorption of molybdoarsenic heteropoly acid (MAA) and its ion pair with tri-n-octylamine (TOA) on sorbents of different nature and hydrophobic filters has been studied. It is demonstrated that MAA is efficiently extracted on the polyacrylate sorbent Amberlyte XAD-8; the distribution coefficient of arsenic is 1 x 10⁴ cm³/g for the sorption from 0.35-1.5 M H₂SO₄. Conditions of the quantitative extraction of MAA in the presence of TOA on thin-layer cellulose triacetate filters are found. A procedure is proposed for the sorption-X-ray fluorescence determination of arsenic in potable water. The detection limit of arsenic is 10 Μg/L for the sorption from 100 mL of a solution.     

Isolation and Characterization of a Non‐Rigid Hexamethylbenzene–SO2+ Complex

During our studies towards the preparation of the pentagonal‐pyramidal hexamethylbenzene dication C₆(CH₃)₆²⁺, we isolated the unprecedented dicationic species C₆(CH₃)₆SO²⁺ (AsF₆⁻)₂ from the reaction of hexamethylbenzene with a mixture of anhydrous HF, AsF₅, and liquid SO₂. This compound can be understood as a complex of unknown SO²⁺ with hexamethylbenzene. Herein, we report on its synthesis, molecular structure, and spectroscopic characterization.     

TiCl(OCH3)(SO3Cl)(OSO2F)-chloro(chlorosulfato)(fluorosulfato)-methoxytitanium(IV) - asymmetric titanium(IV) compound

A stable titanium(IV) compound with four different kinds of ligands, TiCl(OCH₃)(SO₃Cl)? (SO₃F), results when TiCl₂(OCH₃)(SO₃F) is refluxed with HSO₃Cl using CH₂Cl₂ as the solvent. It is an off-white solid and decomposes around 125°C. The powder X-ray diffraction studies of the title compound will be discussed along with other physical and chemical properties.     

THE METASTABLE PARTIALLY POSITIVELY CHARGED Se6 MOLECULE: PREPARATION,CHARACTERISATION AND X-RAY CRYSTAL STRUCTURE OF [Ag2(Se6)(SO2)2][Sb(OTeF5)6]2, [Ag2Se6][AsF6]2 AND [AgSe6][Ag2(SbF6)3]

Reactions designed to give Se₆[Sb(OTeF₅)₆]₂ by the reaction of Se₂Br₂, 4Se, and 2Ag[Sb(OTeF₅)₆] lead to products that include [Ag₂(Se₆)(SO₂)₂][Sb(OTeF₅)₆]₂(1). The distorted cubic (Ag₂Se₆ ²⁺) _n consists of a Se₆ molecule bicapped by two silver cations (local D_3d sym.). Reactions of AgMX₆ (M = As, Sb) with selenium in liquid SO₂ yielded crystals of [Ag₂Se₆][AsF₆]₂ (2) and [AgSe₆][Ag₂(SbF₆)₃] (3). Both salts contain stacked arrays of [AgSe₆]⁺ half-sandwich cationic units. [Ag₂Se₆][AsF₆]₂ in addition contains stronger, linear Se─Ag─Se horizontal linkages between the vertically stacked cationic columns. [AgSe₆][Ag₂(SbF₆)₃] features a remarkable three-dimensional [Ag₂(SbF₆)₃]^? anion held together by strong Sb─F···Ag contacts between component Ag⁺ and SbF₆ ^? ions. Hexagonal channels through this honeycomb-like anion are filled by the stacked [AgSe₆ ⁺]_x.     

Ring Opening Reactions of β-Propiolactam in Superacidic Media

The reaction of β-propiolactam in the superacidic systems HF/MF₅ (M=Sb, As) led to the formation of monoprotonated 3-aminopropanoyl fluoride in the form of [C(O)F(CH₂)₂NH₃][SbF₆] and [C(O)F(CH₂)₂NH₃][AsF₆]. In the presence of traces of water, the diprotonated species β-alanine [C(OH)₂(CH₂)₂NH₃][AsF₆]₂ was synthesized for the first time. All salts were characterized by low-temperature infrared and Raman spectroscopy. Additionally, single-crystal X-ray analyses were conducted in the case of [C(O)F(CH₂)₂NH₃][SbF₆] and [C(OH)₂(CH₂)₂NH₃][AsF₆]₂. By using SO₂ instead of HF as the solvent, the salt [C(OH)₂(CH₂)₂NHSO][SbF₆]₂ was obtained, and single-crystal X-ray analysis of this salt containing a thionylimide moiety was conducted. For the formation of these open-chain compounds, an acyl cationic species as intermediate is assumed, which is formed from N-protonated β-propiolactam. Quantum chemical calculations at the B3LYP/aug-cc-pVTZ and MP2/aug-cc-pVTZ levels of theory were carried out to gain a better understanding of the formation and the structural properties of protonated β-propiolactam.     

Darstellung und Struktur von Tetrafluoro(η5-pentamethylcyclopentadienyl)niob und Tetrafluoro(η5-cyclopentadienyl)niob

Preparation and Structure of Tetrafluoro(η⁵-pentamethylcyclopentadienyl) Niobium and Tetrafluoro(η⁵-cyclopentadienyl) Niobium A facile preparation method for (η⁵-C₅Me₅)NbF₄ 3 and (η⁵-C₅H₅)NbF₄ 4 is reported by using AsF₃ as a fluorinating agent. Single crystals obtained from AsF₃ contain the solvent molecule as well as HF. The composition of the crystal is [(η⁵-C₅Me₅)NbF₄(AsF₃)₂]₂ · [(η⁵-C₅Me₅)NbF₄(HF)AsF₃]₂ 5 . The X-ray crystal structure of 5 will be reported. 5 crystallizes triclinic with one furmula in the space group P1 and lattice constants a = 843.1(4), b = 1154.9(6), c = 1910.2(10) pm, α = 91.68(3)°, β = 99.30(3)°, γ = 104.44(2)°.