Synthesis and Structure of the new Fluoride Bromide Ba6.668(2)Ca0.332(2)F12Br2 and Solid Solutions with Composition Ba7−xCaxF12(ClyBr1−y)2 with x = ∼0.5, 0 < y < 1

Crystals of the chemical composition Ba₇F₁₂Cl₂ were modified by adding a small amount of Ca²⁺ to allow the synthesis of the corresponding bromine compound Ba^[Ca]₇F₁₂Br₂. These samples were prepared in a NaBr flux and characterized by single crystal x‐ray diffraction. The new structure crystallizes in a disordered arrangement in the hexagonal space group P6₃/m (176). The calcium ion has a coordination number of 6. Solid solutions on the heavy halide position can be synthesised in a NaCl/NaBr flux to obtain the compounds Ba_7?xCa_xF₁₂(Cl_yBr_1?y)₂ with x = ～0.5 and 0 < y < 1. Regardless the amount of calcium used in the preparation process, the Ca stoichiometry in the compound is always between 0.3 and 0.5. The lattice parameters differ depending on the Ca‐ and Br‐content between 1053.81(5) ? a = b ? 1058.93(3) pm and 421.21 ? c ? 426.78(3) pm.     

β‐Pyridinium di­chloro­iodide

The β modification of pyridinium di­chloro­iodide, C₅H₆N⁺·Cl₂I^?, was obtained as yellow crystals by the reaction of (C₅NH₅)AuCl₃, C₅H₆N⁺·Cl^? and I₂ in a vacuum‐sealed ampoule. The di­chloro­iodide ion is nearly symmetric and linear with I—Cl bond lengths of 2.544 (3) and 2.550 (3) Å and a Cl—I—Cl angle of 179.68 (12)°.     

The antiestrogen [2‐(4‐benzyl­phenoxy)­ethyl]­diethyl­ammonium chloride

The crystal structure of the title compound, C₁₉H₂₆NO⁺·Cl^? (common name: N,N‐diethyl‐2‐[(4‐phenyl­methyl)phenoxy]‐ethan­amine hydro­chloride), contains one mol­ecule in the asymmetric unit. The planes through the two phenyl rings are roughly perpendicular. Protonation occurs at the N atom, to which the Cl^? ion is linked via an N—H?Cl hydrogen bond. The mol­ecule adopts an eclipsed rather than extended conformation.     

Präparation und Strukturanalyse der Verbindungen Ba2Pb4F10Br2–xIx (x = 0–2) mit verwandten kristallchemischen Motiven aus der Fluoritund Matlockitstruktur

Preparation and Structure of the Compounds Ba₂Pb₄F₁₀Br_2–xI_x (x = 0–2) with Related Structure Motifs of the Fluorites and Matlockites Colourless single crystals of Ba₂Pb₄F₁₀Br_2–xI_x (x = 0–2) have been obtained under hydrothermal conditions (T = 250 °C, 10 d), starting from stoichiometric amounts of BaF₂, PbF₂, PbBr₂ and PbI₂. The compounds crystallize in the tetragonal space group P4/nmm (No. 129). A complete miscibility in the region x = 0–2 has been observed. The mixed crystals follow Vegard's rule. For the compounds with the composition Ba₂Pb₄F₁₀Br₂ (a = 5.9501(2) Å, c = 9.6768(10) Å, R[F² > 2σ(F²)] = 0.022, wR(F² all reflections) = 0.059), Ba₂Pb₄F₁₀Br_1.1I_0,9 (a = 5.9899(3) Å, c = 9.7848(5) Å, R[F² > 2σ(F²)] = 0.014, wR(F² all reflections) = 0.035) and Ba₂Pb₄F₁₀I₂ (a = 6.6417(3) Å, c = 9.9216(10) Å, R[F² > 2σ(F²)] = 0.023, wR(F² all reflections) = 0.049) complete structure analyses have been performed on the basis of single crystal diffractometer data. Microcrystalline single phase compounds Ba₂Pb₄F₁₀Br_2–xI_x (x = 0–2) have been obtained by coprecipitation from aqueous solutions of KF, KBr (KI) and Ba(CH₃COO)₂, Pb(NO₃)₂ in acetic acid medium. For Ba₂Pb₄F₁₀Br_1.5I_0.5 and Ba₂Pb₄F₁₀Br_0.5I_1.5 powder data of microcrystalline samples were used for the Rietveld analyses (R_Bragg = 0.077 for Ba₂Pb₄F₁₀Br_1,5I_0,5 and R_Bragg = 0.065 for Ba₂Pb₄F₁₀Br_0.5I_1.5). The crystal structure comprises alternating structural features of fluorite related type (CaF₂) around Ba and matlockite related type (PbFCl) around Pb1 and Pb2 along the c axis. Barium shows a {8 + 4} cuboctahedral coordination of fluorine. The coordination polyhedron around the two crystallographically independent lead atoms is a monocapped quadratic antiprism built of {4 + 1} fluorine and {4} bromine or iodine atoms, respectively.     

New isotope ratio mass spectrometric method of precise δ37Cl determinations

The most precise method of chlorine isotope analysis described to date is based on the isotope ratio mass spectrometry (IRMS) of chlorine quantitatively converted into chloromethane, CH₃Cl. This gas can be produced from several chlorine‐containing compounds and analyzed by IRMS. However, the mass spectrum of chloromethane is rather complicated and the ratio of the most abundant ions (mass‐52/mass‐50) differs from the ³⁷Cl/³⁵Cl isotope ratio. This difference becomes significant when the δ exceeds 10‰. Moreover, the electron ionization source yields approximately 80% of all the ionic species at the useful masses 50 and 52. To overcome these drawbacks, we have devised a negative ion mass spectrometer which retains all the best features of IRMS, including a dual‐inlet system with changeover valve, dual collector assembly and CH₃Cl gas as analyte. In the modified ion source we have replaced the ionization chamber with an electron beam by a metal tube with a hot metal filament inside it. Within this tube the ³⁵Cl^? and ³⁷Cl^? ions are produced with an efficiency dependent on the filament material and its temperature. No other ionic species were found in the mass spectrum except of traces at masses 26 and 28 at ppm levels, probably due to the formation of CN^? and CO^?. The minimal amount of Cl used in our method is of the order of 5 µmol (3 mg AgCl) and the precision is better than 0.005‰ (1σ). Copyright © 2009 John Wiley & Sons, Ltd.     

EMK-Messungen in binären ladungsunsymmetrischen Salzschmelzen aus Bariumchlorid und Alkalimetallchloriden

EMF Measurements in Binary Chargeunsymmetrical Salt Melts of Barium- and Alkali Chlorides The EMF is measured of cells with transference of the type Cl₂[C]/MCl//MCl? BaCl₂(x)/[C]Cl₂ in the molten mixtures BaCl₂? MCl (M ? Li, Na, K, Rb, Cs). From the EMF values and values of activities from another independent methods the transference numbers of the cations Ba²⁺ and M⁺ relative to the chloride ion in the molten mixtures BaCl₂? (Li, Na, K) Cl are calculated. The values of activities for the system BaCl₂? LiCl are calculated from cryoscopic analysis of the phase diagram.     

4‐Di­methyl­amino­pyridinium bromide

The crystal and molecular structure of 4‐di­methyl­amino­pyridinium bromide, C₇H₁₁N₂^+.Br^?, (I), is built up by hydrogen‐bonded dimers of crystallographic 222 symmetry and four short C—H...halogen contacts. It is remarkable that (I) and 4‐di­methyl­amino­pyridinium chloride are not isostructural.     

Evidence for an indirect halogen exchange in the reaction of trans- 2,3-dibromo-2,3-dihydrobenzofuran with chloride ions

Treatment of the title compound with chloride ions in acetonitrile leads mainly to the formation of trans-2,3-dichloro-2,3-dihydrobenzofuran. Since a nucleophilic displacement of bromide anion by chloride anion can be excluded, a mechanism involving the equilibrium 2Cl^? + Br₂ ? 2Br^? + Cl₂ is suggested.     

Synthese von Oxovanadium(V)‐halogeno‐Komplexen der tripodalen Sauerstoffliganden LR— = [η5‐(C5H5)Co{PR2(O)}3]—, R = OMe,OEt

Syntheses of Oxovanadium(V) Halide Complexes Stabilized with Tripodal Oxygen Ligands L_R^— = [η⁵‐(C₅H₅)Co{PR₂(O)}₃]^—, R = OMe, OEt The sodium salts of the tripodal oxygen ligands L_R^— = [η⁵‐(C₅H₅)Co{PR₂(O)}₃]^— (R = OMe, OEt) react with the oxovanadium halides V(O)F₃ and V(O)Cl₃ to yield deep red compounds of the type [V(O)X₂L_R]. Halide exchange reactions with [V(O)Cl₂L_OMe] und [V(O)F₂L_OMe] aiming at the preparation of the analogous bromide complex [V(O)Br₂L_OMe] led to the isomer [VO(L_OMe)₂][V(O)Br₄]. The crystal structure of [V(O)Cl₂L_OMe] has been determined by single crystal x‐ray diffraction. The compound crystallizes in the monoclinic space group P2₁/n with a = 9.6332(8), b = 15.0312(11) and c = 15.3742(12)Å, β = 100.181(8)°. The coordination around vanadium is distorted octahedral.     

New fluorous ponytailed 4‐[(2,2,2‐trifluoroethoxy)methyl]pyridinium halide salts

It is possible that fluorous compounds could be utilized as directing forces in crystal engineering for applications in materials chemistry or catalysis. Although numerous fluorous compounds have been used for various applications, their structures in the solid state remains a lively matter for debate. The reaction of 4‐[(2,2,2‐trifluoroethoxy)methyl]pyridine with HX (X = I or Cl) yielded new fluorous ponytailed pyridinium halide salts, namely 4‐[(2,2,2‐trifluoroethoxy)methyl]pyridinium iodide, C₈H₉F₃NO⁺·I⁻, (1), and 4‐[(2,2,2‐trifluoroethoxy)methyl]pyridinium chloride, C₈H₉F₃NO⁺·Cl⁻, (2), which were characterized by IR spectroscopy, multinuclei (¹H, ¹³C and ¹⁹F) NMR spectroscopy and single‐crystal X‐ray diffraction. Structure analysis showed that there are two types of hydrogen bonds, namely N—H…X and C—H…X. The iodide anion in salt (1) is hydrogen bonded to three 4‐[(2,2,2‐trifluoroethoxy)methyl]pyridinium cations in the crystal packing, while the chloride ion in salt (2) is involved in six hydrogen bonds to five 4‐[(2,2,2‐trifluoroethoxy)methyl]pyridinium cations, which is attributed to the smaller size and reduced polarizability of the chloride ion compared to the iodide ion. In the IR spectra, the pyridinium N—H stretching band for salt (1) exhibited a blue shift compared with that of salt (2).     

Die Darstellung der Methylthio(trihalogen)phosphonium-Salze ClnBr3−nPSCH3+MF6−(n = 0–3; M = As,Sb) und Hal3PSCH3+SbCl6−(Hal = Br,Cl)

The Preparation of Methylthio(trihalogeno)phosphonium Salts Cl_nBr_3?nPSCH₃⁺MF₆^?(n = 0–3; M = As, Sb) and Hal₃PSCH₃⁺SbCl₆^?(Hal = Br, Cl) The methylthio(trihalogeno) phosphonium salts Br_nCl_3?nPSCH₃⁺MF₆^? (n = 0–3; M = As, Sb) are prepared by methylation of the corresponding thiophosphorylhalides Br_nCl_3?nPS in the system SO₂/CH₃F/MF₅. The hexachloroantimonates Hal₃PSCH₃⁺SbCl₆^?(Hal = Br, Cl) are synthesized by thiomethylation of PBr₃ and PCl₃ with CH₃SCl/SbCl₅. All salts are characterized by vibrational and NMR spectroscopy.     

Synthese und Struktur des μ-Sulfido-μ-disulfido-octabromodiwolframat(V)-Ions [W2S3Br8]2−

Synthesis and Structure of μ-Sulfido-μ-disulfido-octabromoditungstate(V), [W₂S₃Br₈]^?2 Tungsten hexabromide reacts with H₂S in dichloromethane yielding a brown product which, by addition of tetraphenylphosphonium bromide in CH₂Cl₂, is converted to brown, crystalline (PPh₄)₂[Br₄W(μ-S)(μ-S₂)WBr₄] · CH₂Cl₂ · CH₂S. Its IR spectrum is reported, its crystal structure was determined by X-ray diffraction (2330 reflexions, R = 0.097). Crystal data: orthorhombic, Pnma, a = 1 766.5, b = 2 412.7, c = 1 416.3 pm, Z = 4. In the diamagnetic [W₂S₃Br₈]^2? ions the two W atoms are linked via a sulfido and a disulfido bridge and by a W? W bond.     

Structural and Spectroscopic Studies of Halocuprate(I) and Haloargentate(I) Complexes [M2XnX′4−n]2−

The complexes [Cu₂Br₄]^2?, [Cu₂I₄]^2?, [Cu₂I₂Br₂]^2?, [Cu₂I₃Cl]^2?, [Ag₂Cl₄]^2? have been characterized as their isomorphous bis(triphenylphosphoranylidene)ammonium ([Ph₃PNPPh₃]⁺ = PNP⁺) salts by single crystal structural determinations. All anions show the centrosymmetric doubly halogen‐bridged forms [XM(μ‐X)₂MX]^2? with three‐coordinate metal atoms that have been observed in [M₂X₄]^2? complexes with other large organic cations. In [Cu₂I₂Br₂]^2? the iodide ligands occupy the bridging positions and the bromide the terminal positions, while in [Cu₂I₃Cl]^2?, obtained in an attempt to prepare [Cu₂I₂Cl₂]^2?, two of the iodide ligands occupy the bridging positions with the third iodide and the chloride ligand occupying two statistically disordered terminal positions. In [Ag₂Cl₄]^2? the distortion from ideal trigonal coordination of the metal atom is greater than in the copper complexes, but less than in other previously reported [Ag₂Cl₄]^2? complexes with organic cations. The ν(MX) bands have been assigned in the far‐IR spectra, and confirm previous observations regarding the unexpectedly simple IR spectra of [Cu₂X₄]^2? complexes.     

Strong CH⋅⋅⋅Halide Hydrogen Bonds from 1,2,3‐Triazoles Quantified Using Pre‐Organized and Shape‐Persistent Triazolophanes

The structures associated with halide (F^?, Cl^?, Br^?) complexation inside CH hydrogen‐bonding macrocyclic receptors, called triazolophanes, are characterized using density functional theory (DFT). The associated binding energies in the gas and solution phases are evaluated. The ruffles in the empty triazolophane become smoothed‐out upon Cl^?‐ and Br^?‐ion binding directly into the middle of the cavity. The largely pre‐organized cavity morphs into an elliptical shape to facilitate shorter hydrogen bonds in the north and south regions and longer ones west and east. The smaller F^? ion sits in, and flattens‐out, only the north (or south) region. The 1,2,3‐triazoles show shorter CH???Cl^? contacts than for the phenylenes. Both Cl^? and Br^? show the same binding geometries but Cl^? has a larger binding energy consistent with its stronger Lewis basicity. Model triads were used to decompose the overall binding energy into those of its components. In the course of this triad analysis, anion polarization was identified and its contribution to the triad???Cl^? binding energy estimated. Consequently, the binding energies for the individual aryl units within the comparatively non‐polarized triazolophanes were estimated. The 1,2,3‐triazoles are twice as strong as the phenylenes thus contributing most of the interaction energy to Cl^?‐ion binding. Therefore, the 1,2,3‐triazoles appear to approach the hydrogen bond strengths of the NH donors of pyrrole units.     

Bromsulfenyl(trihalogen)phosphonium-Salze Cl3−nBrnPSBr+AsF6− (n = 0 – 3) und Cl3PSBr+SbF6− — Oxidative Bromierung von Thiophosphorylhalogeniden

Bromosulfenyl(trihalogeno)phosphonium Salts Cl_3?nBr_nPSBr⁺AsF₆^? (n = 0 – 3) and Cl₃PSBr⁺SbF₆^? — Oxidative Bromination of Thiophosphorylhalides The bromosulfenyl(trihalogeno)phosphonium salts Cl_3?nBr_nPSBr⁺AsF₆^? (n = 0 – 3) and Cl₃PSBr⁺SbF₆^? are prepared by oxidative bromination of the corresponding thiophosphorylhalides with Br₂/MF₅ (M = As, Sb) and characterized by vibrational and NMR spectroscopy.     

Über die Reaktion von 2,2-Dimethylpropylidinphosphan mit Molybdänpentachlorid; die Kristallstruktur von [Mo2Cl6(α,α′-Dipyridyl)3]

Reaction of 2,2-Dimethylpropylidynephosphine with Molybdenum Pentachloride; Crystal Structure of [Mo₂Cl₆(α,α′-dipyridyl)₃] 2,2-Dimethylpropylidynephosphine and molybdenum pentachloride dissolved in POCl₃ react with oxydation of the phosphorus and reduction of the molybdenum atom to give the alkyne complex [Mo₂Cl₄(μ-Cl)₂(μ-H₉C₄? C?C? C₄H₉)(OPCl₃)₂]. Addition of α,α′-dipyridyl or of methyltriphenylphosphonium chloride in dichloromethane results in a displacement of the ligands POCl₃ and H₉C₄? C?C? C₄H₉ from this complex and in the formation of [Mo₂Cl₆(dipy)₃] or [(H₅C₆? )₃P? CH₃]₃[Mo₂Cl₉]. Besides the latter compound small amounts of [(H₅C₆? )₃P? CH₃]₂[MoCl₆] can be isolated from the reaction mixture. [Mo₂Cl₆(dipy)₃] which has already been prepared by other methods crystallizes in the monoclinic space group P2₁/c with {a = 1612; b = 148; c = 1296 pm; γ 109.3°; Z = 4} at 20°C. As shown by a crystal structure determination the complex is built up from [MoCl₂(dipy)₂]⁺ cations and [MoCl₄(dipy)]^? anions. The molybdenum atoms are both octahedrally surrounded. With average values of 238 and 243 pm the Mo? Cl bond distances in the cation, where a cis-arrangement of the chlorine atoms is observed, and in the anion differ significantly from each other. [Mo₂Cl₆(dipy)₃] which has already been prepared by other methods crystallizes in the monoclinic space group P2₁/c with {a = 1612; b = 148; c = 1296 pm; γ = 109.3°; Z = 4} at 20°C. As shown by a crystal structure determination the complex is built up from [MoCl₂(dipy)₂]⁺ cations and [MoCl₄(dipy)]^? anions. The molybdenum atoms are both octahedrally surrounded. With average values of 238 and 243 pm the Mo? Cl bond distances in the cation, where a cis-arrangement of the chlorine atoms is observed, and in the anion differ significantly from each other.     

Preorganized Anion Traps for Exploiting Anion–π Interactions: An Experimental and Computational Study

1,3‐Bis(pentafluorophenyl‐imino)isoindoline (A^F) and 3,6‐di‐tert‐butyl‐1,8‐bis(pentafluorophenyl)‐9H‐carbazole (B^F) have been designed as preorganized anion receptors that exploit anion–π interactions, and their ability to bind chloride and bromide in various solvents has been evaluated. Both receptors A^F and B^F are neutral but provide a central NH hydrogen bond that directs the halide anion into a preorganized clamp of the two electron‐deficient appended arenes. Crystal structures of host–guest complexes of A^F with DMSO, Cl^?, or Br^? (A^F:DMSO, A^F:Cl^?, and ${{\rm A}{{{\rm F}\hfill \atop 2\hfill}}}$ :Br^?) reveal that in all cases the guest is located in the cleft between the perfluorinated flaps, but NMR spectroscopy shows a more complex situation in solution because of E,Z/Z,Z isomerism of the host. In the case of the more rigid receptor B^F, Job plots evidence 1:1 complex formation with Cl^? and Br^?, and association constants up to 960 M ^?1 have been determined depending on the solvent. Crystal structures of B^F and B^F:DMSO visualize the distinct preorganization of the host for anion–π interactions. The reference compounds 1,3‐bis(2‐pyrimidylimino)isoindoline (A^N) and 3,6‐di‐tert‐butyl‐1,8‐diphenyl‐9H‐carbazole (B^H), which lack the perfluorinated flaps, do not show any indication of anion binding under the same conditions. A detailed computational analysis of the receptors A^F and B^F and their host–guest complexes with Cl^? or Br^? was carried out to quantify the interactions in play. Local correlation methods were applied, allowing for a decomposition of the ring–anion interactions. The latter were found to contribute significantly to the stabilization of these complexes (about half of the total energy). Compounds A^F and B^F represent rare examples of neutral receptors that are well preorganized for exploiting anion–π interactions, and rare examples of receptors for which the individual contributions to the binding energy have been quantified.     

Tetra‐μ‐chloro‐1:2κ4Cl;1:3κ4Cl‐bis(4,4′‐di­methyl‐2,2′‐bi­pyridine)‐2κ2N,3κ2N‐lithium(I)­dipalladium(II) tetrakis­(penta­fluoro­phenyl)­borate di­chloro­methane 1.196‐solvate

In the crystal structure of the title compound, [LiPd₂Cl₄(C₁₂H₁₂N₂)₂](C₂₄F₂₀B)·1.196CD₂Cl₂ or [{(Me₂bipy)PdCl₂}₂(μ‐Li)]⁺·B(C₆F₅)₄⁻·1.196CD₂Cl₂ (Me₂bipy is 4,4′‐di­methyl‐2,2′‐bi­pyridine), an Li⁺ cation is stabilized by complexation with two (Me₂bipy)PdCl₂ units through weak Li—Cl interactions. This compound is thus a rare example of a complex that exhibits an arrested Cl⁻ abstraction.     

Synthesis and crystal structure of tetraethylammonium-μ-trichloro-heptachloro-diaqua-trirhenate(III)-dihydrate,NEt4[Re3Cl10(H2O)2] · 2 H2O

NEt₄[Re₃Cl₁₀(H₂O)₂] · 2 H₂O ( 1 ) was obtained from hydrochloric acid solutions of ReCl₃ and tetraethylammonium chloride, NEt₄Cl, by isothermal evaporation as dark red crystals. 1 crystallizes in the orthorhombic crystal system, space group Pnma, Z = 4, with a = 1838,7(2), b = 1456.9(1), c = 972.08(7) pm, V_m = 391.81(6) cm³ · mol^?l. The crystal structure consists of [Re₃Cl₁₀(H₂O)₂]^? anions that are arranged in the fashion of a hexagonal closest-packing of spheres. These are held together by partially disordered NEt₄⁺ cations and are bound into a hydrogen bonding system with the crystal water.     

DFT Study of the Geometrical and Electronic Structures of Geminal Dicationic Ionic Liquids 1,3‐Bis[3‐methylimidazolium‐1‐yl]hexane Halides

In this work, the geometrical and electronic properties of the mono cationic ionic liquid 1‐hexyl‐3‐methylimidazolium halides ([C₆(mim)]⁺_X^?, X=Cl, Br and I) and dicationic ionic liquid 1,3‐bis[3‐methylimidazolium‐1‐yl]hexane halides ([C₆(mim)₂X₂], X=Cl, Br and I) were studied using the density functional theory (DFT). The most stable conformer of these two types ionic liquids (IL) are determined and compared with each other. Results show that in the most stable conformers, in both monocationic ILs and dicationic ILs, the Cl^? and Br^? anions prefer to locate almost in the plane of the imidazolium ring whereas the I^? anion prefers nearly vertical location respect to the imidazolium ring plan. Comparison of hydrogen bonding and ionic interactions in these two types of ionic liquids reveals that these ionic liquids can be formed hydrogen bond by Cl^? and Br^? anion. The calculated thermodynamic functions show that the interaction of cation — anion pair in the dicationic ionic liquids are more than monocationic ionic liquids and these interactions decrease with increasing the halide anion atomic weight.