Penta‐Ammoniates of Aluminium Halides: The Crystal Structures of AlX3·5NH3 with X = Cl,Br, I

Colourless crystals grow in the colder part of a glass ampoule when AlX₃·5NH₃ with X = Cl, Br, I is heated for 3—6 d to 330 °C (Cl), 350 °C (Br) and 400 °C (I), respectively. The chloride forms hexagonal prisms while the bromide and iodide were obtained as a bunch of lancet‐like crystals. The chloride and bromide crystallize isotypic whereas the iodide has an own structure type. All three are related to the motif of the K₂PtCl₆ type. So the formula of the ammoniates may be written as X₂[Al(NH₃)₅X] ≙ [Al(NH₃)₅X]X₂. The compounds are characterized by the following crystallographic data AlCl₃·5NH₃: Pnma, Z = 4, a = 13.405 (1)Å, b = 10.458 (1)Å, c = 6.740 (2)Å AlBr₃·5NH₃: Pnma, Z = 4, a = 13.808 (2)Å, b = 10.827 (1)Å, c = 6.938 (1)Å AlI₃·5NH₃: Cmcm, Z = 4, a = 9.106 (2)Å, b = 11.370 (2)Å, c = 11.470 (2)Å For the chloride and the bromide the structure determinations were successful including hydrogen positions. All three compounds contain octahedral molecular cations [Al(NH₃)₅X]²⁺ located in distorted cubes formed by the remaining 2X^— ions. The orientation of the octahedra to each other is clearly different for those with X = Cl, Br in comparison to the one with X = I.     

Einkristall-RöntgenStrukturanalysen von Verbindungen mit einer kovalenten Metall-Metall-Bindung. VII. Die Kristall- und Molekülstruktur von dimeren Halogenobis- (pentacarbonylrhenium)indium(III), [(Re(CO)5)2In(μ-X)]2 (X = Cl,Br, I)

Single-Crystal X-Ray Analysis of Compounds with a Covalent Metal-Metal Bond. VII. Crystal and Molecular Structure of the Halogeno-Bridged Dimers of Halogenobis(pentacarbonylrhenium)indium(III), [(Re(CO)₅)₂In(μ-X)]₂ (X = Cl, Br, I) [(Re(CO)₅)₂In(μ-X)]₂ crystallizes if X = Cl and X = Br in the monoclinic system, space group P2₁/c (No. 14), with the lattice constants X = Cl: a = 10.540(6), b = 12.961(7), c = 26.071(12) Å, β = 106.3(1) Å, Z = 4, X = Br: a = 10.548(9), b = 13.108(7), c = 26.192(15) Å, β = 106.0(2)°, Z = 4 and if X = I in the triclinic system, space group P1 (No. 2), with the lattice constants a = 10.739(2), b = 7.160(1), c = 13.647(1) Å, α = 68.65(9), β = 71.89(9), γ = 65.52(9)°, Z = 1. The central molecular fragment consists of a plane In₂X₂ ring with the mean In—X distances: X = Cl: 2.624(6) Å, X = Br: 2.764(3) Å and X = I: 2.986(2) Å and the angles In—X—In/X—In—X, X = Cl: 97.2(2)°/ 82.8(2)°, X = Br: 94.8(1)°/85.2(1)° and X = I: 96.47(5)°/83.53(5)°. Two Re(CO)₅ groups are bonded to each of these In atoms to form a distorted tetrahedral coordination. The mean In—Re bond-distances are: X = Cl: 2.797(2), X = Br: 2.796(2) and X = I:2.811 (2) Å. There is a octahedral coordination around the Re atoms.     

Electronic effects in octahedral π-allyliron complexes: 13C NMR spectra

¹³C NMR spectra have been studied for the three series of allyliron derivatives: (i) C₃HP₅Fe(CO)₃X (X = I, Br, Cl, ONO₂, OCOCH₃, OCOCF₃); (ii) 2-RC₃H₄Fe(CO)₃X (R = CH₃, Br; X = I, Br, Cl, ONO₂, OCOCF₃), and (iii) 1-RC₃H₄Fe(CO)₃X (R = CH₃, C₆H₅; X = Br, Cl, OCOCF₃). The spectra reveal the effect of the nature of the ligand X and substituent R on the chemical shifts of the allyl and carbonyl carbon atoms.     

Kristallstrukturen und Schwingungsspektren von Tetrahalogenoacetylacetonatoosmaten(IV), [OsX4(acac)]−, X  Cl,Br, I

Crystal Structures and Vibrational Spectra of Tetrahalogenoacetylacetonatoosmates(IV), [OsX₄(acac)]^?, X ? Cl, Br, I By reaction of the hexahalogenoosmates(IV) with acetylacetone the tetrahalogenoacetylacetonatoosmates(IV) [OsX₄(acac)]^? (X = Cl, Br, I) are formed, which have been purified by chromatography and precipitated from aqueous solution as tetraphenylphosphonium (Ph₄P) or cesium salts. X-ray structure determinations on single crystals have been performed of (Ph₄P)[OsCl₄(acac)] ( 1 ) (triclinic, space group P1 , a = 9.9661(6), b = 11.208(2), c = 13.4943(7) Å, α = 101.130(9), β = 91.948(6), γ = 96.348(8)°, Z = 2), (Ph₄P)[OsBr₄(acac)] ( 2 ) (monoclinic, space group P2₁/n, a = 9.0251(8), b = 12.423(2), c = 27.834(2) Å, β = 94.259(7)°, Z = 4) and (Ph₄P)[OsI₄(acac)] ( 3 ) (monoclinic, space group P2₁/c, a = 18.294(3), b = 10.664(2), c = 18.333(3) Å, β = 117.68(2)°, Z = 4). Due to the increasing trans influence in the series O < Cl < Br < I the Os? O^. distances of O^.? Cl? X′ axes are lengthened and the OsO^. stretching vibrations are shifted to lower frequencies. The Os? X′ bond lenghts are shorter as compared with symmetrically coordinated X? Os? X axes.     

Elektrochemische synthesen: XXII. Die kathodische reduktion von pentacarbonyl-chrom-halogenphosphanen

The cathodic reduction of the trihalophosphane complexes (CO)₅CrPX₃ (1a, X = Cl; 1b, X = Br) leads to the binuclear complexes (CO)₅ Cr(X₂PPX₂)Cr(CO)₅, (2a, X = Cl; 2b, X = Br). Reductive dehalogenation of coordinated organodihalophosphanes, (CO)₅CrPRX₂ (3a, R = Me, X = Cl; 3b, R = Ph, X = Cl; 3c, R = Me, X = Br; 3d, R = Ph, X = Br), in the presence of dimethyldisulfane yields bis(methylthio)organophosphane complexes, (CO)₅CrPR(SCH₃)₂ (5a, R = Me; 5b, R = Ph). The phosphinidene complexes (CO)₅ CrPR are discussed as the reactive intermediates.The organodibromophosphane complexes 3c and 3d can also be partially reduced in the presence of dimethyldisulfane, and (CO)₅CrPBrR(SCH₃) (7a, R = Me; 7b, R = Ph) is obtained. Radical intermediates are probable.     

Synthesen von aryljod(III)-difluoriden durch direktfluorierung von aryljodiden [1]

The aryl iodides C₆H₅I, o-XC₆H₄I (X = F, I), m-FC₆H₄I and p-XC₆H₄I (X = F, Cl, Br, I, CH₃, NO₂) react with elemental fluorine at about ?100°C in CCl₃F to form the corresponding aryl iodine difluorides without attack on the aromatic ring. Preparations, ¹⁹F-nmr, ¹H-nmr as well as Raman spectra are described.     

Hydrolyse und Halogenidaustausch von Pentahalogenomonocarbonylosmaten(III)

Hydrolysis and Halide Exchange of Pentahalogenomonocarbonyl Osmates(III) The aquo complexes [OsX₄(CO)(H₂O)]^?, [OsX₃(CO)(H₂O)] and [OsX₂(CO)(H₂O)₃]⁺, X ? Cl, Br, I, produced by the stepwise hydrolysis of [OsX₅(CO)]^2?, are isolated as pure solutions by ionophoresis and characterized by their absorption spectra. Due to stability of the monaquo complexes and the different trans-effect of the halides it is possible to prepare the mixed complexes [OsX_4–nY_n(CO)(H₂O)]^?, X ≠ Y = Cl, Br, I, n = 1–3, and for n = 2 the pure stereoisomers are formed. A systematic shift is found in charge-transfer bands to the shorter wavelengths when the halides are replaced by H₂O, I by Br or Cl and Br by Cl.     

Die Ammonolyse von Halogenokomplexen des vierwertigen Platins

Ammonolysis of Halogeno Complexes of Tetravalent Platinum Reactions of liquid ammonia and ammonium hexahalogenoplatinates(IV) at ?40°C yield mixtures of halogenoammine complexes [Pt(NH₃)_6?nX_n]X_4?n (X = Cl, Br, I; n = 3, 2, 1, 0). Hexaammine platinum(IV) salts, [Pt(NH₃)₆]X₄, may be isolated as main product only after several weeks of reaction. Interactions at room temperature of liquid ammonia and hexachloro or hexabromo complexes produce quantitatively the novel dinuclear di-m?-amido-bis[tetraammineplatinum(IV)] complex, [(H₃N)₄Pt(NH₂)₂Pt(NH₃)₄]X₆. By interaction of gaseous or liquid ammonia and subsequent addition of potassium amide solution in excess potassium hexaamido platinate(IV), K₂[Pt(NH₂)₆], is formed in good yield.     

Untersuchungen zum chemischen Transport der Vanadiumoxide V2O5, V3O7 und V6O13

Chemical transport of the vanadium oxides V₂O₅, V₃O₇, and V₆O₁₃ The suitability of water and some halogenating transport agents (NH₄Cl, NH₄Br, I₂) for the chemical transport (temperature gradient 850/750 K) of V₂O₅, V₃O₇, and V₆O₁₃ has been investigated. Transport rates for V₂O₅ and V₆O₁₃ could be measured and reproduced. The best transport agent for V₂O₅ is NH₄Cl or H₂O. For V₃O₇ a combination of the transport agents I₂/H₂O give the best results and for V₆O₁₃ the combination of NH₄Br/H₂O was most appropriate.     

In situ Untersuchungen der Reaktion von Ammoniummonomolybdat, (NH4)2MoO4, mit Ammoniak: Die Struktur von (NH4)2[Mo3O10]

In situ Investigation of the Reaction of Ammonium Monomolybdate (NH₄)₂MoO₄ with Ammonia: The Structure of (NH₄)₂[Mo₃O₁₀] The reactivity of both polymorphs of (NH₄)₂MoO₄ with ammonia was investigated in a temperature range between 20 and 180 °C. Time and temperature controlled X‐ray powder diffraction as well as thermogravimetrical and differential thermal analysis were used to investigate this reaction.The formation of (NH₄)₂[Mo₃O₁₀] from (NH₄)₂MoO₄ is reversible in a humid and irreversible in a dry NH₃ gas flow. Heating (NH₄)₂MoO₄(mP60) under an atmosphere of humid NH₃ at about 170 °C forms (NH₄)₂[Mo₃O₁₀] and succesively cooling yields the (NH₄)₂MoO₄(mS60) polymorph. (NH₄)₂[Mo₃O₁₀] crystallises isostructural to the potassium compound with space group C2/c (No. 15) and lattice constants a = 1398.2(4), b = 804.1(2), b = 921.0(3) pm and β = 98.833(4)°.     

Synthese und Kristallstruktur der Monoammoniakate von Lithiumhalogeniden: LiBr·NH3 und LiI·NH3

Syntheses and Crystal Structures of the Monoammoniates of Lithium Halides: LiBr·NH₃ and LiI·NH₃ Crystals of LiBr·NH₃ and LiI·NH₃ sufficient in size and quality for X‐ray structure determinations were obtained in autoclaves by the reaction of Li with NH₄Br and LiH with NH₄I at 523 K and 423 K respectively. Lattice constants obtained from X‐ray single crystal data are: LiBr·NH₃: P2₁/n, a = 7, 077(2)Å, b = 7, 026(2)Å, c = 7, 490(2)Å β = 114, 84(3)°, Z = 4 LiI·NH₃: P2₁, a = 4, 493(1)Å, b = 6, 077(1)Å, c = 7, 512(2)Å β = 107, 15(3)°, Z = 2 The ammoniates contain different structural building units. Both of them contain layers of connected tetrahedra Li(NH₃)X_3/3 with X = Br, I. Tetrahedra‐double units with a common Br‐Br edge occur, whilst for the iodide all tetrahedra are exclusively vertex connected to puckered layers. IR‐ and Raman‐spectroscopic measurements show, that only weak H‐bridges N‐H···X are present and that the NH₃‐ligands are in fixed positions at room temperature.     

Untersuchungen zu Bismutseltenerdoxidhalogeniden der Zusammensetzung Bi2SEO4X (X = Cl,Br, I)

Investigations on the Bismuth Rare‐Earth Oxyhalides Bi₂REO₄X (X = Cl, Br, I) Compounds of the composition of Bi₂REO₄X (RE = Y, La–Lu; X = Cl, Br, I) have been prepared by solid state reaction of stoichiometric mixtures of BiOX, Bi₂O₃, and RE₂O₃. They were characterized by X‐ray powder diffraction, IR spectroscopy, mass spectrometry and DTA/TG measurements as well. The crystal structure (tetragonal, P4/mmm, a ≈ 3.9 Å, c ≈ 9 Å) was determined by the Rietveld method. In the structure [M₃O₄]⁺ layers are interleaved by single halogen layers. Rare‐earth and bismuth atoms in Bi₂REO₄X are 8‐coordinated. The structure can be derived from the LiBi₃O₄Cl₂ type structure. The enthalpies of formation are derived from heats of solution. The standard entropies were calculated from low‐temperature measurements of the specific heat capacities.     

Synthesis and characterization of 1-Methyl-4-mercaptopiperidine complexes of nickel(II), palladium(II) and platinum(II)

Summary Complexes of formulae Ni(HRS)₂X₂ (X=Cl or Br), M(HRS)₂Y₂ (M=Ni or Pd; Y=NO₂ or C1O₄), Pd(HRS)X₂ (X=Cl, Br or I), Pt(HRS)X₂ (X=Cl or Br), Pt(HRS)₂(ClO₄)₂ and M(RS)₂ (M=Pd or Pt) where HRS and RS denote 1-methyl-4-mercaptopiperidine in the zwitterionic or in the thiolato form, respectively, have been prepared and characterized. In all the complexes the ligands are coordinated exclusively through sulphur. Polymeric structures consisting of square-planar geometry with sulphur-bridged metal atoms are proposed in each case.     

Preparation of Phase Pure Cubic Gallium Nitride, c-GaN, by Ammonothermal Conversion of Gallium Imide, {Ga(NH)3/2} n

Gallium imide, {Ga(NH)_3/2} _n , was sealed in quartz tubes with anhydrous NH₃ and NH₄X (X=Cl, Br, I) and heated vertically in an autoclave with the hot-zone (bottom) temperature ranging from 300–530°C. With NH₄I mineralizer, the imide was converted to primarily the zinc-blende phase of GaN (c-GaN), usually in the form of micron sized or smaller tetrahedra. With NH₄Cl mineralizer, hexagonal GaN nanoparticles formed instead, and NH₄Br facilitated the conversion of imide to irregular h-GaN nanoparticles at lower temperatures, and larger particles above 500°C. At the higher temperatures, chemical transport took place and GaN crystals grew on the walls at the middle to the top of the tube. Most of the deposited GaN was cubic, usually in a heavily etched triangular prismatic morphology. Several experiments were performed in a Pt lined pressure vessel in order to demonstrate that the synthesis method can be scaled up.     

Komplexone XLVI. EDTA-Komplexe des Pt(II)-Ions mit und ohne einzähnige Fremdliganden

The formation of complexes between Pt(II)EDTA^2? and H⁺, OH^?, Cl^?, Br^?, SCN^?, CN^? and NH₃ was investigated using pH and UV.-spectrophotometric measurements at ionic strength 1.0 and 25°. The existence of the following species could be proved (charges are omitted): H_pPt(EDTA) (0 ≤ p ≤ 3), Pt(EDTA)X (X = OH, NH₃, Cl, Br, I, SCN), H_pPt(EDTA)X (1 ≤ p ≤ 3; X = Cl, Br) and H₄Pt(EDTA)Cl₂. They have been characterised by spectral data as well as with equilibrium constants. The different modes of attachment of EDTA are discussed.     

Synthese und strukturelle Charakterisierung von Borsubphthalocyaninaten

Synthesis and Structural Characterization of Boron Subphthalocyaninates Halosubphthalocyaninatoboron, [B(X)_spc] (X = F, Cl, Br) is obtained by heating phthalonitrile with boron trihalide in quinoline (X = F) or the corresponding halobenzene, resp. [B(C₆H₅)_spc] is prepared from phthalonitrile and tetraphenylborate or tetraphenyloboron oxide, resp. [B(OR)_spc] (R = H, CH(CH₃)₂, C(CH₃)₃, C₆H₅) is synthesized by bromide substitution of [B(Br)_spc] in pyridine/HOR. Substitution of [B(Br)_spc] in carboxylic acids yields [B(OOCR)_spc] (R = H, CX₃ (X = H, Cl, F), CH₂X (X = Cl, C₆H₅), C₆H₅). All subphthalocyaninates are characterized electrochemically and by UV‐VIS, IR/FIR, resonance Raman, and ¹H/¹⁰B‐NMR spectroscopy. Typical B–X stretching vibrations are at 622 (X = Br), 950 (Cl), 1063 (F), 1096 cm^–1 (OH) as well as between 1119 and 1052 cm^–1 (OR) resp. 985 and 1028 cm^–1 (OOCR). The difference ν(C=O)–ν(C–O) > 400 cm^–1 confirms the unidentate coordination of the carboxylato ligands. According to the crystal structure analysis of [B(OH)_spc], [B(OH)_spc] · 2 H₂O, [B(C₆H₅)_spc], [B(OC(CH₃)₃)_spc], [B(OOCCH₃)_spc] · 0.5 H₂O · C₂H₅OH and [B(OOCCH₃)_spc] · 0.4 H₂O · 1.1 C₅H₅N the _spc ligand is concavely distorted. This saucer shaped conformation is independent of the acido ligands and the presence of solvate. The outermost C atomes are vertically displaced in part by more than 2 Å from the N_i plane. The B atom is in a distorted tetrahedral coordination geometry. It is displaced by ca 0.64 Å out of the N_i plane towards the acido ligand. The average B–N distance is 1.500 Å, and the B–O distances range from 1.418(5) to 1.473(2) Å.     

Dissolution of copper and gold in the donor-acceptor systems DMSO-NH4Xaq (X = Cl, Br, and I) and NH4Iaq-O2

The dependences of the dissolution rate of copper on the ratio of components of the liquid phase (DMSO and NH₄X_aq, where NH₄X_aq is an aqueous solution of NH₄X; X = Cl, Br, and I) were studied in aqueous-organic donor-acceptor systems DMSO-NH₄X_aq systems by the resistometric method. The method involves measurements of the electroresistance of a metal sample in the course of the reaction. The pattern of the dependences observed under the conditions of free air access shows that the process rates mzximize at the molar ratio of the components NH₄X: DMSO = 0.05: 0.95 (gC = Cl, Br, and I) and minimize at the ratio 0.5: 0.5 (for gC = Cl and Br). The second maximum is detected at the ratio NH₄I: DMSO = 0.8: 0.2 for the DMSO-NH₄I_aq system. The inorganic donor-acceptor system NH₄I_aq-O₂ was found to efficiently dissolve copper and gold.     

Strukturen von neuen Bis(pentafluorophenyl)halogenomercuraten [{Hg(C6F5)2}3(μ‐X)]— (X = Cl,Br, I)

Structures of New Bis(pentafluorophenyl)halogeno Mercurates [{Hg(C₆F₅)₂}₃(μ‐X)]^— (X = Cl, Br, I) From the reactions of [PNP]Cl or [PPh₄]Y (Y = Br, I) with Hg(C₆F₅)₂ crystals of the composition [Cat][{Hg(C₆F₅)₂}₃X] (Cat = PNP, X = Cl ( 1 ); Cat = PPh₄, X = Br ( 2 ), I ( 3 )) are formed. 1 crystallizes in the triclinic space group P1¯, 2 and 3 crystallize isotypically in the monoclinic space group C2/c. In the crystals the halide anions are surrounded by three Hg(C₆F₅)₂ molecules. The reaction of [PPh₄]Br with Hg(C₆F₅)₂ under slightly changed conditions gives the compound [PPh₄]₂[{Hg(C₆F₅)₂}₃(μ‐Br)][{Hg(C₆F₅)₂}₂(μ‐Br)] ( 4 ).     

Density functional theory study on the reactions of X− with CH3SY (X,Y = F,Cl, Br,I)

Gas‐phase anionic reactions X^? + CH₃SY (X, Y = F, Cl, Br, I) have been investigated at the level of B3LYP/6‐311+G (2df,p). Results show that the potential energy surface (PES) of gas‐phase reactions X^? + CH₃SY (X, Y = Cl, Br, I) has a quadruple‐well structure, indicating an addition–elimination (A–E) pathway. The fluorine behaves differently in many respects from the other halogens and the reactions F^? + CH₃SY (Y = F, Cl, Br, I) correspond to deprotonation instead of substitution. The gas‐phase reactions X^? + CH₃SF (X = Cl, Br, I), however, follow an A–E pathway other than the last two out going steps (COM2 and PR) that proceeds via a deprotonation. The polarizable continuum model (PCM) has been used to evaluate the solvent effects on the energetics of the reactions X^? + CH₃SY (X, Y = Cl, Br, I). The PES is predicted to be unimodal in the solvents of high polarity. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007     

Untersuchungen zur thermischen Zersetzung der Ammoniumyttriumhalogenide I. Ammoniumyttriumchloride

Investigation on the Thermal Decomposition of Ammonium Yttrium Halides. I. Ammonium Yttrium Chlorides (NH₄)₃YCl₆ decomposes in first step to the solid phase NH₄Y₂Cl_7,s and gaseous NH_3,g and HCl_g. NH₄Y₂Cl_7,s decomposes in a second step to YCl₃, NH₃ and HCl. The decomposition-pressure-functions are given and from this the enthalpies of formation and the standard entropies of the phases are derived.