Showing papers in "Zeitschrift für Naturforschung B in 1996"

Ligand influences on the supramolecular chemistry of simple gold(i) complexes : mononuclear (isonitrile)gold(i) complexes

Abstract: Abstract A series of (isonitrile)gold(I) complexes has been synthesized: (MeNC)AuX (X = Cl la, I lc), (t-BuNC)AuBr 2b. (PhNC)AuX (X = Cl 3a. Br 3b. I 3c. SCN 3d), (MesNC)AuCl 4a [mes=mesityl], and (MeOC(O)CH2NC)AuX (X = Cl 5a. Br 5b. I 5c. SCN 5d). The chlorides were prepared by the reaction of (Me2S)AuCl with equimolar amounts (or with an excess) of the corresponding isonitrile. The bromides, iodides and thiocyanates were obtained from the reaction of (RNC)AuCl with K+X- (X = Br, I, SCN) in the two-phase system H2O/CH2CI2. The molecular and crystal structures of la. 2b. 3a-c, 4a, and 5a-c have been determined by X-ray diffraction methods. In the solid state the molecules are aggregated through short Au-Au contacts into dimers (4a and 5c), chains (la, 2b and 3a-c) or sheets (5a and 5b). The influence of the isonitrile and halide ligands on the type and strength of the intermolecular Au-A u contacts is discussed

Zur Umsetzung von Bis(η5-cyclopentadienyl)dihydridowolfram mit Halogenboranen / On the Reaction of Bis(η5-cyclopentadienyl)tungstendihydride with Boran Halides

Abstract: Bis(η5 -cyclopentadienyl)tungstendihydride reacts with iPr2BCl, BCl3 or BF3 to give the saltlike compounds [Cp2WH3]iPr2BCl2 (1a), [Cp2WH3]BCl4 (b), and [Cp2WH3]BF4 (c) with a bis(η5-cyclopentadienyl)trihydridotungsten cation and a borate anion. Compound 1a crystallizes in the space group P21/n.

Crystal structure and magnetic susceptibility of ce8pd24sb

Abstract: : The ternary compound Ce8Pd24Sb is very close in composition to the intermediate valent binary Cepd3. A single crystal study yielded a cubic cell with a=8.461(1)A, Pm3m symmetry with wR2=0.0412 based on 1453 reflections (222 unique) and 16 parameters. This new structure type is composed of distorted perovskite and Cu3Au subcells arranged with the perovskite-like units centered on the corners of the cube. Fitting the magnetic susceptibility data above 100K to a Curie-Weiss expression yielded a Weiss constant of -15(3)K (anti-ferromagnetic) and an effective high temperature moment per cerium of 2.45(4)microB indicating trivalent behavior of the cerium atoms. No ordering was observed above 3K. jg

Quaternary Thorium Transition Metal Pnictide Oxides: ThCu1-xPO, ThCuAsO, and Th2Ni3-xP3O

Abstract: Abstract The new compounds ThCu1-xPO and ThCuAsO with ZrCuSiAs-type structure were prepared in well crystallized form by chemical vapor transport reactions. Th2Ni3-xP3O with a new structure type was obtained by reaction of ThO2 with the other elemental components in an alumina crucible at high temperatures. The crystal structures of the three compounds were determined from single-crystal X-ray data. ThCu1-xPO: P4/nmm, a = 389.43(4), c -828.3(1) pm, R = 0.024 for 13 variable parameters and 338 structure factors; ThCuAsO: P4/ nmm, a = 396.14(5), c = 844.0(1) pm, R = 0.028 (13 variables and 379 F values); Th2Ni3-xP3O : P4/nmm, a = 394.62(4), c = 1723.2(3) pm, R = 0.018 (27 variables and 374 F values). The refinement of the occupancy parameters revealed significant deviations from the ideal values for the transition metal sites for two compounds resulting in the exact compositions ThCu0.938(4)PO and Th2Ni2.45(1)P3O . Magnetic susceptibility measurements indicate Pauli paramagnetism for ThCu1-xPO . The crystal structures of these compounds are closely related. They belong to a large family of tetragonal structures of which the ThCr2Si2-and the PbFCl-type structures are well known examples.

1,3,4,5-Tetramethyl-2-methylenimidazolin - ein Olefin mit Ylid-artigen Eigenschaften [1] / 1,3,4,5-Tetramethyl-2-methylenimidazoline - an Olefin with Ylidic Properties [1]

Abstract: A facile synthesis of l,3,4,5-tetramethyl-2-methylenimidazoline 5 (Im) starting from the pentamethylimidazolium ion (8) and KH is described. Boranes react with 5 to give the adducts ImBHi3 (11) and ImBF3 (18). With Mel and CH3C(O)Cl the imidazolium salts ImMe+ (19) and ImC(O)Me+ (20) are obtained. CS2 gives the zwitterionic compound ImCS2 (24) which is transformed into the cationic thiocarboxylic ester ImC(S)SCH2Cl+ on treatment with CH2Cl2. Reaction with chlorotrimethylsilane gives the imidazolium ion ImSiMe+3 (26) which may be transferred into the disilylated imidazolium ion 28 via deprotonation and subsequent silylation, the silylated olefin 27 being the intermediate. Similarly, the cations ImSiR2Cl+ (29; R = Me, Ph) are obtained from 5 and the silanes R2SiCl2. The neutral adduct ImSnPh2Cl2 (32) is formed in the reaction of 5 with Ph2SnCl2. Iodine reacts with 5 to give the charge-transfer adduct Iml2 (35), which can be further transferred into the imidazolium salt Iml+I-3 (36).

Metallkomplexe mit funktionalisierten Schwefelliganden, X [1] Ruthenium(II)-und Platin(II)-1-alkin-1-thiolato-Komplexe. Kristallstrukturanalyse von trans-(Ph3P)2Pt[S-C≡C-C(CH3)3]2 / Metal Complexes of Functionalized Sulfur Containing Ligands, X [1] Synthesis of Ruthenium (II) and Platinum(II) 1-Alkyne-1-thiolato Complexes. X-Ray Structure Analysis of trans-( Ph3P)2Pt[C-C≡C-C(CH3)3]2

Abstract: The 1-alkyne-1-thiolates R-C ≡C-SLi [1a: R = C(CH₃)₃, 1b: R = C₆H₁₁ ] react with L₂PtCl₂ (L = PPh₃, 1/2 dppe) and CpRu(PPh₃)₂Cl, respectively to give the complexes trans-(Ph₃P)₂Pt[S-C ≡C-C(CH₃)₃]₂ (2a), cis-dppePt[S-C≡C-C(CH₃)₃]₂ (2b), and CpRu(PPh₃)₂-(S-C ≡ C-R) [3a: R = C(CH₃)₃, 3b: R = C₆H₁₁]. 2a has been characterized by ³¹P CP/MAS NM R spectroscopy and its crystal structure determined by X-ray diffraction.

Neue Pnictide mit modifizierten AIB2-Strukturen / New Pnictides with Modified AIB2-Type Structures

Abstract: Abstract Nine new compounds AMX with A: Ca, Sr, Ba, M: Pd, Au and X:P, As were prepared by heating mixtures of the elements and investigated by Xray methods. They crystallize in modified AIB2- type structures, for the present examples in the ZrBeSi- and SrPtSb-types, with an ordered distribution of the atoms

(1,3-Diethyl-1,3-dihydro-4,5-dimethyl- 2H -imidazol-2-yliden)-diiodtellur(II) [1]

Abstract: Abstract The carbene adduct 5 is formed from the 2-tel-luroimidazoline 4 and iodine. The X-ray structure analysis reveals a dimeric structure in the solid state.

Die Kristallstrukturen der Dysprosium-Komplexe [DyCl3(DME)2] und [DyCl2(THF)5]+[DyCl4(THF)2]- / Crystal Structures of the Dysprosium Complexes [DyCl3(DME)2] and [DyCl2(THF)5]+[DyCl4(THF)2]-

Abstract: Abstract [DyCl3(DME)2] (DME = 1,2-dimethoxyethane) has been prepared from the known tetrahy-drofuran complex [Dy2Cl6(THF)7] in boiling DME. Both complexes were characterized by structure determinations. [DyCl3(DME)2]: Space group P21/c, Z = 4, lattice dimensions at -70 °C: a = 1141.9(6), b = 884.2(4), c = 1558.3(6) pm, β = 104.83(4)°. The complex has a molecular structure with a distorted pentagonal bipyramidal geometry in which the oxygen atoms of the chelating DME molecules and one chlorine atom occupy the pentagonal plane. [DyCl2(THF)5]+[DyCl4(THF)2]-: Space group C2/c, Z = 4, lattice dimensions at -70 °C: a -1241.4(9), b = 1139.4(6), c = 2735.1(19) pm, β = 91.19(4)°. The complex contains a seven-coordinate cation with axial chloride ligands in a pentagonal bipyramidal structure and a six-coordinate anion with a trans octahedral geometry.

Polynuclear gold(i) complexes of mercaptocarboxylic acids

Abstract: In a search for air-stable and water-soluble mercapto compounds of gold with a high gold content, benzylthiol, a-m ercapto-acetic acid, β-mercapto-propionic acid, and thiosalicylic acid were converted into aurated sulfonium salts by treatment with reagents of the type [(R₃P)Au]₃O⁺ BF₄⁻ or [(R₃)P)Au]⁺ BF₄⁻. - BzSH served as a mono-functional model thiol, which was converted into BzS[Au(PMe₃)]₂⁺ BF₄⁻ (1). The small tertiary phosphine was chosen in order to minimize steric effects. In the crystal the cations are associated into centrosymmetrical dimers through short Au-A u contacts (auriophilicity). - The two carboxylic acids with thiol functions, HSCH₂COOH and HSCH₂CH₂COOH, gave triply aurated species of the type {[(Ph₃P)Au]₂S(CH₂)nCOOAu(PPh₃)}⁺ BF₄⁻ (2: n = 2, 3; n = 3). The crystal structure analysis of the representative compound 2 showed again the presence of centrosymmetrical cation dimers with geometrical details of the sulfonium part of the molecules very similar to those of the reference compound 1. In addition, the carboxyl groups in 2 and 3 bear a (phosphine)gold unit mono-hapto bound at one of the oxygen atoms. -2-HS-C₆H₄-COOH was converted into a sulfonium salt {[(Ph₃P)Au]₂S-C₆H₄-COOH}⁺ BF₄⁻ (4), which crystallizes free of solvent from dry dichloromethane, and as a monohydrate with one mole of dichloromethane (4a = 4 H₂O-CH₂CI₂) from hydrous CH₂CI₂. In the solvent-free crystalline phase (4) the cations are associated into dimers with the usual intermolecular double A u-A u contacts, but in 4a there are monomeric cations with the water molecule hydrogen-bonded to the carboxylic acid function

Dicyanometallate, VII [1] Darstellung und Kristallstruktur von Gadolinium-tris-dicyanoaurat (I), Gd[Au(CN)2]3·2,3H2O / Dicyano Metallates, VII [1] Preparation and Crystal Structure of Gadolinium-tris-dicyanoaurate (I), Gd[Au(CN)2]3·2,3H2O

Abstract: The title compound has been prepared by adding a stoichiometric amount of gadolinium nitrate hexahydrate to an aqueous solution of potassium dicyanoaurate(I). Single crystals could be obtained by slow evaporation from the saturated solution. The compound crystallizes hexagonally, space group P-62m, with a = 6.6319(6), c = 9.108(2) Å, c/a = 1.3734 and Z = 1. The structure comprises layers of considerably bent dicyanoaurate groups. The gold atoms form a nearly regular 3.6 .3.6 - Kagomé net with a layer sequence AA.. and an Au - Au distance of 3.316(2) A, i. e. remarkably shorter than that found in KAu(CN)2 (Au - Au = 3.652(1) Å). Above and below the gold layers, the terminal nitrogen atoms of the dicyanoaurate groups build up a two- dimensional net work in the a,b plane, thereby creating trigonal- prismatic holes, which are occupied by the gadolinium ions. Up to three water molecules per unit cell complete the coordination sphere around the gadolinium ion to form a tricapped trigonal prism. The analogous compounds with Ln = Sm, Eu, Tb and Dy are obviously isostructural with the Gd compound, as can be inferred from preliminary X-ray studies.

Synthesis, Infrared and X-Ray Studies of Diphenyltellurium(IV) Nitrosocarbamylcyanmethanides. X-Ray Evidence for Stability of a Tritelluroxane Fragment -Ph2Te-O-Ph2Te-O-Ph2Te-

Abstract: Abstract Diphenyltellurium(IV) derivatives of the types Ph2Te{ACO}2 (1), Ph4Te2O{ACO}2 (2) and Ph6Te3O2{ACO} (3) (ACO = nitrosocarbamylcyanmethanide -ONC(CN)C(O)NH2) have been prepared. The IR spectroscopic data reveal that the ambidentate ligands are coordinated to the tellurium(IV) atom in a monodentate manner via the nitroso oxygen atom. The crystal and molecular structure of 3 has been determined from X-ray diffraction data (triclinic, space group P1̅ with a = 12.382(2), 6=13.100(2), c = 14.944(3) Å, a = 87.74( 1), β = 85.04(2), 7 = 66.29( 1)°, V = 2211.0 A , Z = 2, R = 0.040). The structure is made up of unsymmetric molecules, in which the tellurium atoms are linked by oxo bridges to form chains Te-O-Te-O-Te (d(Te-O) ca. 1.94-2.09 A). The Te-0 (nitroso group) bond lengths are in the range 2.33 - 2.36 Å

Labilisierung einer Carboxylgruppe der koordinierten Triethylentetramin- N, N, N′,N″, N‴, N‴ -hexaessigsäure (H6ttha): Koordinationszahlen 10 für [La(H ttha)]2- und 9 für [Dy(Httha)]2- in ihren Guanidiniumsalzen / Labilizing of a Carboxyl Group o f the Coordinated Triethylenetetramine-N, N, N′ ,N″, N‴, N‴ - hexaacetic Acid (H6ttha): Coordination Numbers 10 for [La(Httha)]2- and 9 for [Dy(Httha)]2- in their Guanidinium Salts

Abstract: The lanthanum(III) and dysprosium(III) complexes of triethylenetetramine-N, N, N′, N″, N‴, N‴-hexaacetic acid (H6ttha) were prepared and isolated as guanidinium salts:[C(NH2)3]2[La(Httha)] · 3 H2O and [C(NH2)3]2[Dy(Httha)] · 5 H2O. The X-ray crystal structure of both complexes was determined: In the La(III) complex (space group P1̄) all donor atoms (N4O6) are coordinated. The coordination number 10 is realized in a bicapped square antiprism (SAPRS-10). The bond length La to O of the protonated carboxylic group is ca. 0.3 Å longer than the other five La-O distances. The Dy(III) complex (space group P1̄) exhibits coordination number 9 in a monocapped square antiprism (SAPRS-9). The protonated carboxylic group is not coordinated.

Supram olekulare chloridverbrückte Metall(II)chlorid-Diazin-Komplexe: Kristallstrukturen von [Cd(pyrazin)Cl2], [Zn(pyrazin)Cl2] und [Zn(pyrimidin)C l2] / Supram olecular Chloride Bridged Metal(II) Dichloride Diazine Complexes: Crystal Structures of [Cd(pyrazine)Cl2], [Zn(pyrazine)Cl2], and [Zn(pyrimidine)Cl2]

Abstract: Single crystals of [Cd(pyrazine)Cl₂],[Zn(pyrazine)Cl₂] and [Zn(pyrimidine)Cl₂] were obtained by a diffusion technique from aqueous solutions of the metal dichlorides and solutions of the respective diazine.The structures consist of “supramolecular” networks of-M-Cl-M - and -M-diazine-M-chains.

Preparation and Structure of Poly(gold)telluronium Salts

Abstract: Abstract Tris[(triphenylphosphine)gold(I)]telluronium tetrafluoroborate (1) was prepared from the corresponding oxonium salt and bis(t-butyldimethylsilyl)tellurium in dichloromethane at -78°C. The product forms yellow crystals, thermally stable to 125°C. It was identified by standard analytical and spectroscopic techniques, including a single crystal X-ray diffraction study. In the crystal lattice, the cations form tellurium-capped triangles of gold, which are associated into dimers through short intermolecular Au -Au contacts, resembling those in the corresponding sulfur and selenium compounds. - The reaction of (t-BuMe2Si)2Te with four equivalents of [(Ph3P)Au]BF4 in tetrahydrofuran at -78°C gives a tetranuclear compound, {[(Ph3P)Au]4Te}2+ 2 BF4- (2) which differs from 1 in its analytical and spectroscopic data. Its structure could not be determined, but it is assumed that the dications have a square pyramidal geometry

Structure and spin-spin interactions in a linear trinuclear ni(ii) complex

Abstract: [Ni₃(C₂H₃O₂)₂(C₃H₈NO)₂L₂] [(L=N,N′-1,3-propyl-disalicylaldimine), (C₂H₃O₂)=acetate, (C₃H₈NO)=hydroxymethyl-dimethylamine] has been synthesized and its crystal structure determined, [C₄₄H₅₄N₆O₁₀Ni₃], triclinic, space group P1, a = 9.560(1), b = 10.681(1), c = 12.200(1) A, α = 112.17(1), β = 101.25(1), γ = 90.32(1)°, V = 1127.3 A, Z = 1.The molecule is linearly trinuclear with octahedral coordination of each nickel ion. The Ni-Ni distance is 3.048(1) A. Each nickel(II) atom is in an octahedral coordination. Magnetic susceptibility measurements in the range 4.2 < T < 280 K have revealed antiferromagnetic coupling between adjacent Ni atoms (J₁ = -2.2 cm⁻¹) and between the terminal Ni atoms (J₂ = -1.7 cm⁻¹).

Syntheses and Properties of Cerium Diphthalocyanines in High Oxidation States; Crystal Structure of [Ce(Pc)2](BF4) 0.33

Abstract: Ring oxidized green Cerium(IV)diphthalocyanines, [Ce(Pc)₂]X (X = (poly)halide, NO₃⁻) are prepared by chemical oxidation of (ⁿBu₄N)[Ce(Pc²⁻)₂] with the corresponding halogen in solution or of solid [Ce(Pc²⁻)₂] with aqueous HNO₃ Electrochemical oxidation of (nBu₄N)[Ce(Pc²⁻)₂] in solution in the presence of (ⁿBu₄N)BF₄ yields [Ce(Pc)₂](BF₄)₀.₃₃, which crystallizes in the tetragonal space group P4/nnc (a, b = 19.643(3) A, c = 6.525(3) A, Z = 2). The Ceᴵⱽ ion is eightfold coordinated by the isoindole N atoms (Nᵢₛₒ) of the two staggered (ca. 41°), slightly distorted Pc ligands. The “[Ce(Pc)₂]⁰.³³⁺” subunits are arranged in infinite columns along [001] with the Ce atoms statistically disordered over two positions and Ce - Nᵢₛₒ bond lengths of 2.45(1) and 2.69(1) A, respectively The UV-VIS spectrum is dominated by the transitions of the Pc²⁻ ligand at ca. 15,000 (B band), 30,000 and 36,000 cm ⁻¹ (Q, N region). A low energy (“metallic”) band at ca. 2800 cm ⁻¹ typical for partially oxidized systems is present. The UV-VIS-NIR spectrum of [Ce(Pc)₂]NO₃ indicates a cofacial Pc²⁻ - P c⁻ complex. In addition to the π-π’ transitions of the Pc²⁻ moiety at ca. 14,000, 30,000 and 36,000 cm⁻¹, the Ch transition of the Pc- ring is observed at ca. 19,200 cm ⁻¹ and the typical NIR band at 6380 cm ⁻¹. Oxidation of a thin film of (PNP)[Ce(Pc²⁻)2] with dry Br₂/ N₂ gas yields purple [Ce(Pc⁻)₂]Brₓ, whose UV-VIS-NIR spectrum shows the diagnostic features of dimeric Pc⁻ radicals with intense bands at ca. 14,000 and 18,000 cm ⁻¹ assigned as B and Q₁ bands, respectively. At ca. 9000 cm⁻¹ the typical QD absorption is observed. The vibrational spectra are dominated by the transitions of the Pc⁻ ligand at 1305/1445 cm ⁻¹ (IR) and 560/1120/1172/1591 cm⁻¹ (resonance Raman). Excitation with 1064 nm strongly enhances the sym. C e-N stretch at 163 c m ⁻¹.

New Preparative Methods for the Halides of Titanium(II) and Vanadium(II): Reduction of Titanium(IV) Halides with Sodium and Oxidation of Bis(mesitylene)vanadium(0)

Abstract: Abstract TiCl4(THF)2 reacts with two equivalents of sodium in THF to afford the soluble TiCl2(THF)n (1), which has been characterized analytically and by spectroscopic and magnetic measurements. By redox reactions. TiCl2(THF)n gives TiCl2(9,10-C10H8O2) (2), or TiCl2(benzoate)2 .(3), with 9,10-phenanthrenequinone or dibenzoylperoxide in toluene, respectively. By operating in 1,2-dimethoxyethane (DME), Na(DME)1.5[TiCl4(DME)] (4), or NaTiCl3(DME)2 have been isolated from the reaction of TiCl4(DME) with one or two equivalents of sodium, respectively. From 4, by cation exchange, PPN[TiCl4(DME)] [PPN = bis(triphenylphosphine)iminium] (5), has been obtained and characterized analytically, spectroscopically and by X-ray diffraction methods. Crystal data: C40HCl4NO2P2Ti. MW = 818.4, space group: Pna21 (N° 33). a = 14.445(2), b = 15.690(2), c = 17.544(2) Å . V = 3976(2) Å3, Z = 4, F(000) = 1692, R = 0.041, Rw = 0.0420. The titanium(III) atom in the anion has the expected cis-octahedral, slightly distorted, geometry. By reaction of TiBr4(DME)0.5 with sodium in DME, TiBr3(DME)1.5 .1.5 DM E (7), is the product. Bis(mesitylene)vanadium(0), Vmes2, reacts with two equivalents of CPh3Cl in DME, to give VCl2(DME)n.

Untersuchungen an Polyhalogeniden, XXV [1]. Triiodide von Pyridinkomplexen des zweiwertigen Palladiums: Dipyridinpalladiumhexaiodid Pd(py)2I6 und zwei Formen des Tetrapyridinpalladiumhexaiodids Pd(py)4I6 / Studies on Polyhalides, XXV [1]. Triiodides of Pyridine Complexes of Divalent Palladium: Di(pyridine)palladium Hexaiodide Pd(py)2I6 and Two Forms of Tetra(pyridine)palladium Hexaiodide Pd(py)4I6

Abstract: Two forms of the new compound Pd(py)4I6 have been prepared by the reaction of stoichiometric amounts of PdCl2, C5H5N, KI and I2 in water. One modification crystallizes triclinically in space group Ρ1̄ with a = 907.7(3), b = 960.5(7), c = 992.0(4) pm, α = 117.31 (4), β = 103.35(3), γ = 86.01(5)° and Z = 1, the other orthorhombically in space group Pnnm with a = 891.6(4), b = 1047.6(4), c = 1659.1(5) pm and Z = 2. Both structures may be described as layerlike packings of I3- anions and [Pd(py)4]2+ cations. Differences arise from the orientations of the anions and cations within these layers. The new compond Pd(py)2l6 has been prepared by recrystallisation of Pd(py)4I6 from chloroform. It crystallizes in the monoclinic space group I2/a with a = 1801.1(4), b = 584.0(1), c = 2220.5(6) pm, β = 115.78(2)° and Z = 2. The structure is built up from quasi square planar complexes [Pd(py)2l2] and iodine molecules I2 linked together to give alternating screw- and zigzag-shaped chains ^[I_-I2] along [1 0 01 forming nets of type (10, 3) including the Pd2+ ions. The structure may also be described as a layerlike packing of the anionic chains 1∞[I- · I2] and linear complex cations [Pd(py)2]2+ parallel [0 1 1].

Methanolothermale Synthese und Kristallstruktur von Tetraselenidoarsenaten( V) und -antimonaten(V) des Rubidiums und Cäsiums / Methanolothermal Synthesis and Crystal Structure of Tetraselenidoarsenates(V) and -antimonates(V) of Rubidium and Cesium

Abstract: Abstract Tetraselenidoarsenates(V) and -antimonates(V), Rubidium, Cesium, Methanolothermal Synthesis, Crystal Structure Methanolothermal reaction of M2CO3 (M = Rb, Cs) with E2Se3 (E = As, Sb) and Se at temperatures in the range 180 -200°C leads to the formation of tetraselenidoarsenates(V) and -antimonates(V) M3ESe4 in moderate to quantitative yields. All four compounds crystallize in the (NH4)3AsS4 structure type (space group Pnma) and contain isolated slightly distorted tetrahedral ESe3-4 anions with crystallographic CS symmetry. Both of the independent cations are coordinated in an irregular manner by seven Se atoms.

Intramolekular-stabilisierte Organogallium-und -indiumhalogenide. Ein erstes neutrales Indiumhydrid

Abstract: The intramolecularly coordinating 2-(dimethylaminomethyl)phenyl-(X) and 4-terr-butyl-2,6-bis(dimethylaminomethyl)phenyl-(Y) ligands were employed in the preparation of the gallium and indium halides: X₂InI (B), XInI₂ (1), X₂InBr (2), XInBr₂ (3), XIn(Et)I (4), XGaI₂ (6) and YInI₂ (7). The first neutral indium hydride X₂InH (5) was made in situ from LiInH₄ and 2. Z₂InCl (8) (Z = 2-pyridyl-bis(trimethylsilyl)methyl), and X₃Ga (C) were also synthesized. The compounds are characterized by N. M. R. (¹H, ¹³C, ²⁹Si and for 6 ⁷¹Ga) and mass spectrometry and elemental analyses or peak matching M. S.. N. M. R.-data are discussed as well as the X-ray structure analyses provided for B, 2, 4, 5, 7 and 8.

Gold(i) complexes of chiral secondary phosphines

Abstract: The reaction of (dimethylsulfide)gold(I) chloride and bromide with methyl(phenyl)phosphine in ṯetraẖydrof̱uran affords high yields of the colorless, crystalline, chiral complexes [Me(Ph)HP]AuCl/Br ( 1a, b). Treatment of la with potassium iodide in thf leads to a conversion into the corresponding iodide [Me(Ph)HP] Aul ( 1c). The compounds were characterized by their analytical and spectroscopic data, and the crystal structures of la, b have been determined. The two compounds are isomorphous. In the lattice the monomers form chain-like supramolecular aggregates through auriophilic Au-Au contacts. The chains contain both enantiomers following the sequence ..R S R S R S.., with the individual components related by crystal symmetry.

Reaktion von Ph3P=C=PPh3 mit Fe(CO)5; Molekülstrukturen von (CO)4Fe=C=C=PPh3 und Fe3(CO)9 (μ3 -η2-C≡C-PPh3) / Reaction of Ph3P=C=PPh3 with Fe(CO)5; Molecular Structures of (CO)4Fe=C=C=PPh3 and Fe3(CO)9(μ3 -η2-C≡C-PPh3)

Abstract: The ylide Ph3P=C=PPh3 reacts with Fe(CO)5 in toluene to give the metallacumulene (CO)4Fe=C=C=PPh3 (1) and O=PPh3. A mixture of the ylide with its hydrolysis product Ph2P(O)-CH=PPh3 produces the trinuclear cluster Fe3(CO)9(μ3-η2-C≡CPPh3) (2) in low yields which can also be obtained from 1 and Fe2(CO)9. Both compounds contain the same ligand bonded in a terminal (1) and in a bridging (2) manner. 1 and 2 crystallize in the monoclinic space groups P2(1)/n and P2(1)/c, respectively, with the unit cell parameters a = 1008.35(10), b = 1167.89(10), c = 1875.10(10) pm, β = 99.824(10)° for 1 and a = 853.6(2), b = 1966.6(4), c = 1770.2(4) pm; β = 99.05(3)° for 2. The compounds are further characterized by IR and NMR (13C ,31P) spectroscopy and elemental analyses.

Notizen: Die Kristallstruktur von Calciumchromat(VI), CaCrO4 / The Crystal Structure of Calcium Chromate (VI), CaCrO4

Abstract: The zircon-type structure of calcium chromate( VI), CaCrO4, has been confirmed and refined from single-crystal X-ray data. The compound crystallizes tetragonaly, space group I41/amd, with a = 7.222(2), c = 6.285(1) Å, c/a = 0.8703 and Z = 4. The structure comprises isolated, slightly distorted CrO4 tetrahedra ( C r-O = 1.646(3) Å ) which are connected with CaO8 dodecahedra ( = 2.556 Å) by edge- and corner-sharing. The three-dimensional framework thus created contains rather large holes which are, however, empty in the case of CaCrO4

Preparation and Crystal Structure of the Isotypic Carbides Ln3.67TC6 (Ln = rare earth elements; T = Mn, Fe, Ru) and Eu3,16NiC6

Abstract: Abstract The 14 carbides Ln3.67MnC6 (Ln = La-Nd) and Ln3.67TC6 (Ln = La-Nd, Sm; T = Fe, Ru) were prepared from the elemental components by arc-melting and subsequent annealing. Eu3.16NiC6 was obtained from a lithium flux. The crystal structures of these nearly isotypic, hexagonal compounds (P63/m, Z = 2) were determined from single-crystal X-ray data; La3.67- FeC6: a = 878.7(2), c = 535.1(1) pm, R = 0.052 for 548 structure factors and 25 variable parameters; Eu3.16NiC6: a -860.0(1), c = 548.2(2) pm, R = 0.015 for 606 structure factors and 25 variables. The structures differ from the previously reported Gd3Mn2C6 structure by the occupancy of one manganese position by rare earth atoms. Since the lanthanum atoms are larger than the manganese atoms, only two thirds of these manganese positions can be occupied by the lanthanum atoms in La3.67FeC6. Eu3.16NiC6 has similar atomic positions. The C-C bond distances in the C2 pairs are 130(2) and 126.5(5) pm in the La and Eu compounds, respectively. Magnetic susceptibility measurements with a SQUID magnetometer indicate La3.67FeC6 to be Pauli paramagnetic. A test for superconductivity was negative down to 3 K.

Darstellung und Charakterisierung von N(CH2PPh2)3, N(CH2PPh2)3Mo(CO)3 und [HN(CH2PPh2)3Mo(CÖ)3]BF4 / Preparation and Characterisation of N(CH2PPh2)3,N(CH2PPhi)3Mo(CO)3 and [HN(CH2PPh2)3Mo(CO)3]BF4

Abstract: The synthesis of N(CH2PPh2)3 (1) and its spectroscopic properties are reported. Reaction of N(CH2PPh2)3 with (CH3CN)3Mo(CO)3 leads to N(CH2PPh2)3Mo(CO)3 (2). The cationic complex [HN(CH2PPh2)3Mo(CO)3]+ (3) is obtained by protonating the N atom of 2 with aqueous HBF4. The spectroscopic and structural properties of 2 and the cation 3 are compared. The results indicate an interaction of the ligand N atom and the Mo atom through space over more than 350 pm. It is shown from IR data that 2 is fixed on silicagel by hydrogen bonding.

Zweidimensionales Eis und H5O2+-Ionen. Zur Bildung und Struktur tiefschmelzender molekularer und ionischer Hemi-bis Hexahydrate halogenierter Essigsäuren CClnF3-nCOOH (n = 1 bis 3) [1] / Two-Dimensional Ice and H5O2+ Ions. On Formation and Structure of Low-Melting Molecular and Ionic Hemi-through Hexahydrates of Haloacetic Acids CClnF3-nCOOH (n = 1 to 3) [1]

Abstract: Abstract Hydrate formation of haloacetic acids CClnF3-nCOOH (n = 1, 2, 3) has been studied by DTA and temperature-dependent X-ray powder diffraction, and evidence obtained for five phases, all melting at temperatures below ambient. The hydrates have been confirmed and further characterized by their crystal structures at -150 °C. Three lower hydrates, CCl2FCOOH· 0.5H2O (space group P21/c and Z = 8 formula unites per unit cell), CClF2COOHH2O (P21/c, Z = 4), and CClF2COOH ·4H2O (P1̄, Z = 2), have molecular structures with the acid and water molecules hydrogen-bonded in two-dimensional arrays. The structures of the remaining hydrates, CCl2FCOOH·6H2O and CCl3COOH · 6H2O (similar, but not isotypic, both P1̄ and Z = 2), are ionic, as (H5O2+)(CX3COO-) · 4H2O , and three-dimensional. The neutral water molecules are hydrogen-bonded in ice-like layers rare in crystal chemistry. Also, CCl2FCOOH is established only as the second acid of which a lower hydrate is molecular and a higher one ionic.

Neue Synthesewege zu neutralen gemischtsubstituierten Eisen-Schwefel-Clustern / Novel Synthetic Pathways to Neutral Mixed-Ligand Iron-Sulfur Clusters

Abstract: The reaction of [Fe(NiSiMe3)2)2] with thiols RSH, elemental sulfur, and neutral ligands L (with sulfur donor atoms, e. g. thiourea derivatives) gives [Fe4S4(SR)2L2] clusters in high yields. The structure of [Fe4S4(2.4.6-(C3H7)3C6H2-S)2(dpdmi)2] (dpdmi: diisopropyldimethyl- imidazolthion) was determined by X-ray crystallography. When [Fe4S4I4]2- is reacted with a large excess of PMePh2 or PMe2Ph [F6S6I2(PMePh2)4] and [Fe6S6l2(PMe2Ph)4]. respectively, are obtained in nearly quantitative yield. Basket-like structures of the [Fe6S6]2+ cores were detected by X-ray structure analysis. While [Fe4S4(SR)4]2- clusters do not react with phosphanes at ambient temperature 2:2 functionalized species like [Fe4S4(SR)2(tmtu)2] lead to basket-type clusters [Fe6S6(SR)2(PR3)4].