Darstellung der Halogeno-Pyridin-Rhenate(III), [ReX6−n (Py)n](3−n)− (X = Br,Cl; n = 1−3), sowie Kristallstrukturen von trans-[(C4H9)4N][ReBr4(Py)2], mer-[ReCl3(Py)3] und mer-[ReBr3(Py)3]

Preparation of Halogeno Pyridine Rhenates(III), [ReX_6?n(Py)_n]^(3?n)? (X = Br, Cl; n = 1?3) Crystal Structures of trans-[(C₄H₉)₄N][ReBr₄(Py)₂], mer-[ReCl₃(Py)₃], and mer- [ReBr₃(Py)₃] The mixed halogeno-pyridine-rhenates(III), [ReX_6?n(Py)_n]^(3?n)? (X = Br, Cl), n = 1?3, have been prepared for the first time by reaction of the tetrabutylammoniumsalts (TBA)₂[ReX₆] (X = Br, Cl) in pyridine with (TBA)BH₄ and separation by chromatography on Al₂O₃. Apart from the monopyridine complexes only the trans and mer isomers are formed from the bis-and tris-pyridine compounds. The X-ray structure determinations of the isotypic neutral complexes mer- [ReX₃(Py)₃] (monoclinic, space group P 2₁/n, Z = 4; for X = Cl: a = 9,1120(8), b = 12,5156(14), c = 15,6100(13) Å, β = 91,385(7)°; for X = Br: a = 9,152(5), b = 12,852(13), c = 15,669(2) Å, β = 90,43(2)°) reveal, due to the stronger trans influence of pyridine compared with Cl and Br, that the Re? X distances in asymmetric Py? Re? X3 axes with ReCl3 = 2,397 Å and ReBr3 = 2,534 Å are elongated by 1,3 and 1% in comparison with symmetric X1? Re? X2 axes with ReCl1 = ReCl2 = 2,367 Å and ReBr1 = 2,513 and ReBr2 = 2,506 Å, respectively. The Re? N bond lengths are roughly equal with 2,12 Å. Trans-(TBA)[ReBr₄(Py)₂] crystallizes triclinic, space group P1 , a = 9,2048(12), b = 12,0792(11), c = 15,525(2) Å, α = 95,239(10), β = 94,193(11), γ = 106,153(9)°, Z = 2. The unit cell contains two independent but very similar complex anions with approximate D_2h(mmm) point symmetry.     

Darstellung,Kristallstrukturen, Schwingungsspektren und Normalkoordinatenanalysen von trans-(PNP)[TcCl4(Py)2] und trans-(PNP)[TcBr4(Py)2]

Preparation, Crystal Structures, Vibrational Spectra, and Normal Coordinate Analysis of trans-(PNP)[TcCl₄(Py)₂] and trans-(PNP)[TcBr₄(Py)₂] By reaction of (PNP)₂[TcX₆] with pyridine in the presence of [BH₄]^? (PNP)[TcX₄(Py)₂], X = Cl, Br, are formed. X-ray structure determinations on single crystals of these isotypic Tc^III complexes (monoclinic, space group P2₁/n, Z = 2, for X = Cl: a = 13.676(4), b = 9.102(3), c = 17.144(2) Å, β = 91.159(1)°; for X = Br: a = 13.972(2), b = 9.146(3), c = 17.285(4) Å, β = 90.789(2)°) result in the averaged bond distances Tc? Cl: 2.386, Tc? Br: 2.519, Tc? N: 2.132(3) (X = Cl) and 2.143(4) Å (X = Br). The two pyridine rings are coplanar and vertical to the X? Tc? X-axes, forming angles of 42.28° (X = Cl) and 43.11° (X = Br). Using the molecular parameters of the X-ray structure determination and assuming D_2h point symmetry, the IR and Raman spectra are assigned by normal coordinate analysis based on a modified valence force field. Good agreement between observed and calculated frequencies is obtained with the valence force constants f_d(TcCl) = 1.45, f_d(TcBr) = 1.035, f_d(TcN) = 1.37 (X = Cl) and 1.45 mdyn/ Å (X = Br), respectively.     

The crystal and molecular Structure of Trans-MoCl3(C5H5N)3

Trans-MoCl₃Py₃ (Py 7mdash; pyridine) crystallizes in the monoclinic space group P2₁/c with four molecules in the unit cell. The cell dimensions are: a = 9.229(3), b = 12.555(3), c = 17.920(4) Å and β = 119.33(2)°. Calculated density for Z = 4 is 1.61 gcm^?3 and measured 1.61 ± 0.02 gcm^?3. Structure has been solved from 1594 independent film data and refined to the conventional R factor 9.1%. Three chlorine atoms and three nitrogen atoms of the pyridine molecules form an octahedral coordination about molybdenum in the 1, 2,6 or trans configuration. Distances within octahedron are: Mo? Cl 2.437(5), 2.424(5), 2.423(5) Å, and Mo? N(pyridine) 2.189(13), 2.163(15), 2.223(15) Å. CrCl₃Py₃, CrBr₃Py₃ and MoBr₃Py₃ crystallize in the same space group with comparable cell dimensions and are probably isostructural with trans-MoCl₃Py₃.     

Synthesis of trans,trans-[MoX2py4][MoX4py2], trans-[MoX2py4]Br3, and structural identification of trans,trans-[MoX2py4][MoX4py2] (X = Cl,Br; py = pyridine)

Trans,trans-[MoX₂py₄][MoX₄py₂] (X = Cl, A; Br, B; py = pyridine, C₅H₅N) are the side products of reaction of between (NH₄)₂[MoX₅ · H₂O] (X = Cl,Br) with pyridine diluted with methanol. Both trans,trans-[MoX₂py₄][MoX₄py₂] are monoclinic, P2₁/n space group, with z = 2 and: a = 12.568(1), b = 9.430(1), c = 14.952(1) Å and β = 100.81(1)° (A); a = 12.551(2), b = 9.533(2), c = 15.366(2) (Å) and β = 99.35(1) (B). Cations and anions are located on the symmetry centers and have eclipsed conformation of the trans located pyridine ligands. Average Mo? X and Mo? N (pyridine) bonds are; (cation) 2.41, 2.21 Å (A); 2.54, 2.21 Å (B); (anion) 2.44, 2.20 Å (A); 2.58, 2.20 Å (B). Anionic part of the compounds can be oxidised by bromine to trans-MoX₄py₂, which precipitates from the solution. Cation can be isolated from the solution in the form of trans-[MoX₂py₄]Br₃ (X = Cl, Br). The compounds were also characterised by chemical analysis, infrared spectroscopy and conductivity measurements.     

Solid-state vibrational spectroscopy: Part VI. An infrared and raman spectroscopic study of transition metal(II)4-methylpyridine complexes

Infrared (4000–200 cm^?1) and Raman (3500–300 cm^?1 ) spectra are reported for metal(II) halide and thiocyanate 4-methylpyridine complexes of the following stoichiometries: (MX₂(4-Mepy)₂) {M = Mn, Co, Cu or Zn, X = Cl or Br; M = Mn, Ni or Zn, X = NCS}; (MX₂(4-Mepy)₄) {M = Mn, Fe, Co or Ni, X = Cl or Br; M = Mn, Fe, Co, W or Cu, X = NCS}. For a given series of isomorphous complexes there is a correlation between the sum of the differences between the liquid and ligand values of the ν₁, ν₂, ν₃, ν₄, ν₅, ν₆, ν₇, ν₈, ν₉, ν₁₀, ν₁₂, ν₁₃ and ν₁₄ modes of 4-methylpyridine and the strength of the metal-nitrogen bond. Comparison of the shift values of pyridine and 4-methylpyridine complexes supports the suggestion that, unlike the situation in the pyridine complexes, back-donation from the metal to the ligand is unimportant in the 4-methylpyridine complexes.     

Darstellung,Kristallstrukturen, Schwingungsspektren und Normalkoordinatenanalysen der Tetrahalogeno‐bis‐Pyridin‐Osmium(III)‐Komplexe cis‐(n‐Bu4N)[OsCl4Py2] und trans‐(n‐Bu4N)[OsX4Py2], X = Cl,Br

Synthesis, Crystal Structures, Vibrational Spectra, and Normal Coordinate Analyses of the Tetrahalogeno‐bis‐Pyridine‐Osmium(III) Complexes cis ‐( n ‐Bu₄N)[OsCl₄Py₂] and trans ‐( n ‐Bu₄N)[OsX₄Py₂], X = Cl, Br By reaction of (n‐Bu₄N)₂[OsX₆], X = Cl, Br, with pyridine and (n‐Bu₄N)[BH₄] tetrahalogeno‐bis‐pyridine‐osmium(III) complexes are formed and purified by chromatography. X‐ray structure determinations on single crystals have been performed of cis‐(n‐Bu₄N)[OsCl₄Py₂] ( 1 ) (triclinic, space group P1, a = 9.4047(9), b = 10.8424(18), c = 17.007(2) Å, α = 71.833(2), β = 81.249(10), γ = 67.209(12)°, Z = 2), trans‐(n‐Bu₄N)[OsCl₄Py₂] ( 2 ) (orthorhombic, space group P2₁2₁2₁, a = 8.7709(12), b = 20.551(4), c = 17.174(4) Å, Z = 4) and trans‐(n‐Bu₄N)[OsBr₄Py₂] ( 3 ) (triclinic, space group P1, a = 9.132(3), b = 12.053(3), c = 15.398(2) Å, α = 95.551(18), β = 94.12(2), γ = 106.529(19)°, Z = 2). Based on the molecular parameters of the X‐ray structure determinations and assuming C₂ point symmetry for the anion of 1 and D_2h point symmetry for the anions of 2 and 3 the IR and Raman spectra are assigned by normal coordinate analysis. The valence force constants of 1 are in the Cl–Os–Cl axis f_d(OsCl) = 1.58, in the asymmetrically coordinated N′–Os–Cl ^· axes f_d(OsCl ^· ) = 1.45, f_d(OsN′) = 2.48, of 2 f_d(OsCl) = 1.62, f_d(OsN) = 2.42 and of 3 f_d(OsBr) = 1.39 and f_d(OsN) = 2.34 mdyn/Å.     

Darstellung,Kristallstrukturen, Schwingungsspektren und Normalkoordinatenanalysen der mer‐Trihalogeno‐tris‐Pyridin‐Osmium(III)Komplexe mer‐[OsX3Py3], X = Cl,Br, I

Synthesis, Crystal Structures, Vibrational Spectra, and Normal Coordinate Analyses of the mer ‐Trihalogeno‐tris‐Pyridine‐Osmium(III) Complexes mer‐[OsX₃Py₃], X = Cl, Br, I By reaction of the hexahalogenoosmates(IV) with pyridine and iso‐amylalcohol mer‐trihalogeno‐tris‐pyridine‐osmium(III) complexes are formed and purified by chromatography. X‐ray structure determinations on single crystals have been performed of mer‐[OsBr₃Py₃] (monoclinic, space group P2₁/n, a = 9.098(5), b = 12.864(5), c = 15.632(5) Å, β = 90.216(5)°, Z = 4) and mer‐[OsI₃Py₃] (monoclinic, space group P2₁/n, a = 9.0952(17), b = 13.461(4), c = 15.891(10), β = 91.569(5)°, Z = 4). The pyridine rings are twisted propeller‐like against the N₃ meridional plane with mean angles of 49° (Cl), 46° (Br), 44° (I). Based on the molecular parameters of the X‐ray structure determinations and assuming C₂ point symmetry, the IR and Raman spectra are assigned by normal coordinate analysis. Due to the stronger trans influence of pyridine as compared with the halide ligands for N'–Os–X ^· axes significantly different valence force constants are observed in comparison with symmetrically coordinated octahedron axes: f_d(OsCl) = 1.74, f_d(OsCl^·) = 1.49, f_d(OsBr) = 1.43, f_d(OsBr ^· ) = 1.18, f_d(OsI) = 0.99, f_d(OsI ^· ) = 0.96, f_d(OsN) between 1.96 and 2.07 and f_d(OsN') between 2.13 and 2.32 mdyn/Å.     

Fluorine Containing Coordination Compounds of CrIII. I. Crystal and Molecular Structure of trans-[Cr(en)2F2] · ClO4

Trans-[Cr(en)₂F₂]ClO₄ (en = 1,2-diaminoethane) has triclinic P1 space group with a = 5.633(1), b = 8.879(2), c = 11.686(2) Å, α = 99.92(2), β = 87.22(2), γ = 100.02(2)° and Z = 2. The unit cell contains two independent trans-Cr(en)₂F₂⁺ cations and ClO₄^? anion. Average Cr? F bond length is 1.88(1) Å. Cr? N bonding distances are from 2.05 to 2.10 Å. Mean Cl? O distance is 1.36 Å. 1,2-diaminoethans are in the gauche conformation. Trans-[Cr(en)₂F₂]Cl and [Cr(en)₂F₂]Br have monoclinic and orthorhombic space groups with four equivalent Cr(en)₂F₂⁺ cations. Trans-[Cr(en)₂F₂]I forms twinned crystals preventing further crystallographic investigation.     

Synthese und Eigenschaften von Bis(tetra(n-butyl)ammonium)-μ-carbidodi(halogenophthalocyaninato(2–)ferraten(IV)); Kristallstruktur von Bis(tetra(n-butyl)ammonium)-μ-carbidodi(fluorophthalocyaninato(2–)ferrat(IV))-Trihydrat

Synthesis and Properties of Bis(tetra(n-butyl)ammonium)μ-Carbido-di(halophthalocyaninato(2–)ferrates(IV)); Crystal Structure of Bis(tetra(n-butyl)ammonium) μ-Carbido-di(fluorophthalocyaninato(2–)ferrate(IV)) Trihydrate μ-Carbido-di(pyridinephthalocyaninato(2–)iron(IV)) reacts with tetra(n-butyl)ammonium halide (ⁿBu₄N)X) in solution (X = F) or in a melt (X = Cl, Br) to yield bis(tetra(n-butyl)ammonium μ-carbido-di(halophthalo-cyaninato(2–)ferrat(IV)). The fluoro-complex salt crystallizes as a trihydrate monoclinically in the space group P12₁/n1 with the following cell parameters: a = 15.814(1) Å; b = 22.690(5) Å; c = 25.127(3) Å; β = 98.27(1)°, Z = 4. The Fe atoms are almost in the centre (Ct) of the (N_iso)₄ planes (N_iso: isoindoline-N atom) with a Fe–Ct distance of 0.053(1) Å. The average Fe–N_iso distance is 1.939(4) Å, the Fe–(μ-C) distance 1.687(4) Å and the Fe–F distance 2.033(2) Å. The Fe–(μ-C)–Fe core is linear (179.5(3)°). The pc²-ligands are staggered (φ = 42(1)°) with a convex distortion. The asymmetric Fe–(μ-C)–Fe stretch (in cm^–1) is observed in the IR spectra at 917 (X = F), 918 (Cl) and 920 (Br) and the symmetric Fe–(μ-C)–Fe stretch at 476 cm^–1 in the resonance Raman spectra. The IR active asymmetric Fe–X stretch (in cm^–1) absorbs at 336 (X = F), 203 (Cl), 182 (Br), respectively.     

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.     

Die Reaktion von [Mo6Cl8]X4 mit N-Basen

Reaction of [Mo₆Cl₈]X₄ with N-Bases [Mo₆Cl₈]X₄ (X = Cl, Br, I) in ethanol solution by titration with Ag⁺ showed 4 labil X atoms. The displacement of X^? especially by F^? accelerates the titration decisively. Conductivity measurements in ethanol or acetone showed that [Mo₆Cl₈]X₄ at 25°C behave as weak 1:1-electrolytes. Solutions of [Mo₆Cl₈]X₄ in DMF heated up to 60°C and than lowered to 25°C showed that the compounds in this solvent behave as (potential) strong 2:1-valent electrolytes. From the following compounds the labil halides have been determined by titration with Ag⁺: [Mo₆Cl₈]X₄(Py)₂ (X = Cl, Br), [Mo₆Cl₈]X₄(bipy)₂ (X = Cl, Br, I), [Mo₆Cl₈]X₄(Phenpy)₂ (X = Cl, Br, I), (PyH)₂[Mo₆Cl₈]X₆ (X = Cl, Br); (bipyH)₂[Mo₆Cl₈]I₄Cl₂. Always 4 (respectively 6) labil halides have been observed; exception [Mo₆Cl₈]Cl₄(Py)₂ in acetone (2 labil Cl). Lattice constants and mole volumina for the adducts with pyridin and bipyridin have been determined. The adducts with bipyridin and phenylpyridin are isotypic. Conductivity measurements have been made in different solutions. The decomposition on the thermobalance showed that in [Mo₆Cl₈]Cl₄(Py)₂ the bond of pyridin is weak. The 2 pyridin molecules are evolved at the same time. However [Mo₆Cl₈]I₄(Bipy)₂ loses 1 bipyridin only. (PyH)₂[Mo₆Cl₈]X₆ formed during the first decomposition step the novel compounds (PyH) [Mo₆Cl₈]X₅ (X = Cl, Br). Both compounds are isotypic. They behave in ethanol solution as strong 1:1-valent electrolytes.     

Structural Characterization of trans-[Cr(NH3)4(H2O)Cl]Cl2 and trans-[Cr(NH3)4Cl2]l

Trans-[Cr(NH₃)₄(H₂O)Cl]Cl₂ (A) crystallizes in the monoclinic space group P2₁/m (No. 11) with a = 6.556(1), b = 10.630(5), c = 6.729(2) Å and β = 96.15(3)°. Trans-[Cr(NH₃)₄Cl₂]I (B) has monoclinic C2/m (No. 12) space group and a = 9.877(2), b = 8.497(2), c = 6.047(2) Å and β = 108.98(2)°. Both unit cells contain two formula units. Cr? Cl, Cr? O(H₂O) and three independent Cr? N(NH₃) distances for A are 2.98(1), 2.023(2), 2.067(2), 2.086(3) and 2.064(3) °. Cr? Cl and Cr? N(NH₃) bonds in B are 2.325(1) and 2.071(2) °. All octahedral angles are close to 90 and 180°. Both structures were refined to very low R values. Water molecule from trans-[Cr(NH₃)₄(H₂O)Cl]²⁺ is hydrogen bonded to both ionic chlorides. Cation and two anions form the motive which repeats itself in the crystal. Cations and anions of the second structure are distributed in layers. Each cation and anion have coordination number eight.     

The preparation and spectral properties of the new ‘mixed’ complexes [MI2(CO)3(py)L] (M = Mo and W; L = PPh3, AsPh3 and SbPh3)

Abstract

Seven-coordinate complexes of molybdenum(II) and tungsten(II) have become increasingly important as homogeneous catalysts. For example, the complexes [MX₂(CO)₃L₂] (M = Mo and W; X = Cl and Br; L = PPh₃ and AsPh₃) have been shown to be catalysts for the ring-opening polymerisation of norbornene.¹ Although a wide variety of complexes of the type [MX₂(CO)₃L₂] (M = Mo and W; X = Cl, Br and I; L = nitrogen, phosphorus, arsenic and antimony donor ligands)² have been reported, until now no examples of the mixed complexes [MX₂(CO)₃(py)L] have been prepared. In this communication we wish to describe the synthesis of the new mixed pyridine/L compounds [MI₂(CO)₃(py)L] (M = Mo and W; L = PPh₃, AsPh₃ and SbPh₃).     

Magnesiumphthalocyanine: Darstellung und Eigenschaften von Halogenophthalocyaninatomagnesat, [Mg(X)Pc2−]− (X = F,Cl, Br); Kristallstruktur von Bis(triphenylphosphin)iminiumchloro(phthalocyaninato)magnesat-Aceton-Solvat

Magnesium Phthalocyanines: Synthesis and Properties of Halophthalocyaninatomagnesate, [Mg(X)Pc^2?]^? (X = F, Cl, Br); Crystal Structure of Bis(triphenylphosphine)iminiumchloro-(phthalocyaninato)magnesate Acetone Solvate Magnesium phthalocyanine reacts with excess tetra(n-butyl)ammonium- or bis(triphenylphosphine)iminiumhalide ((ⁿBu₄N)X or (PNP)X; X = F, Cl, Br) yielding halophthalocyaninatomagnesate ([Mg(X)Pc^2?]^?; X = F, Cl, Br), which crystallizes in part as a scarcely soluble (ⁿBu₄N) or (PNP) complex-salt. Single-crystal X-ray diffraction analysis of ^b(PNP)[Mg(Cl)Pc^2?] · CH₃COCH₃ reveals that the Mg atom has a tetragonal pyramidal coordination geometry with the Mg atom displaced out of the center (Ct) of the inner nitrogen atoms (N_iso) of the nonplanar Pc ligand toward the Cl atom (d(Mg? Ct) = 0.572(3) Å; d(Mg? Cl) = 2.367(2) Å). The average Mg? N_iso distance is 2.058 Å. Pairs of partially overlapping anions are present. The cation adopts a bent conformation (^b(PNP)⁺: d(P1? N(K)) = 1.568(3) Å; d(P2? N(K)) = 1.587(3) Å; ?(P1? N(K)? P2) = 141.3(2)°). Electrochemical and spectroscopic properties are discussed.     

Adducts of coordination compounds-XIII. Nitrates,hydrogen and silver dinitrates,and polysilver nitrates of trans-dihalotetrakispyridinerhodium(III) and iridium(III) ions

The synthesis and characterization, chiefly as salts of the anions [X(ONO₂)₂]⁻ (X = H⁺ or Ag⁺) (by analysis, X-ray powder photography, vibrational spectra and thermogravimetry) of adducts of the nitrates trans-[M(L)₄X₂](NO₃) (M =Rh or Ir; L = pyridine, perdeuteriopyridine or 4-methylpyridine; X = Cl or Br) with hydrogen nitrate and silver nitrate are described.     

Etude structurale par spectrometrie infrarouge et raman des composes de coordination: bis(pyridine)- trichloro aluminium(III) et bis(pyridine)tribromo aluminium(III)

The compounds AlX₃-2Py (X = Cl or Br, Py = C₅H₅N or C₅D₅N) have been prepared by using a method based on an exchange of organic ligands. The infrared and Raman spectra, which have been recorded between 50 and 4000 cm^?1, give strong evidence for the existence of the anion AlCl₄^? (or AlBr₄^?) and show that the cation is AlX₂(Py)⁺₄. The comparison of the spectra with those of the compound NiX₂(Py)₄., and of the cations trans-AlX₂(THF)₄⁺ and cis-AlX₂(bipy)₂⁺ indicates that the cation AlX₂(Py)₄⁺ has the helical configuration (helical trans-octahedron) and allows the assignment of the vibrations.     

Zinc(II), cadmium(II) and mercury(II) complexes of 4,6-dimethyl-pyrimidine-2(1H)-one

The following zinc(II), cadmium(II) and mercury(II) complexes of 4,6-dimethylpyrimidine-2(1H)-one (L) have been prepared and investigated by conductometric,IR and Raman methods: MX₂L₂ (M = Zn, X = Cl, Br(CHCl₃, I(CHCl₃, CF₃COO; M = Cd, X = Cl, Br CF₃COO; M = Hg, X = Cl, CF₃COO), Cd₂I₄L₃, Hg₃X₆L₂ (X = Cl, Br), Hg₃X₆L₄(X = Br, I), MX₂L₄·6H₂O (M = Zn, Cd, X = CIO₄, BF₄; M = Hg, X = CIO₄. The ligand is principally bonded through the unprotonated nitrogen atom and in some complexes also through the carbonylic oxygen atom. The zinc halide complexes are tetrahedrally coordinated, the trifluoroacetate ion is coordinated as a monodentate ligand.     

Coordination compounds of ethylhydrazine and 2,2,2-Trifluoroethylhydrazine; crystal and molecular structure of dichlorotetrakis(2,2,2-Trifluoroethylhydrazine) nickel(II)

Ethylhydrazine (EH) forms the complexes MX₂(EH)₂ (M = Co, Ni; X = Cl; M = Co, X = Br), NiBr₂(EH)₂(H₂O) and MX₂(EH) (M = Zn, Cd; X = Cl; M = Zn, X = Br). Spectroscopic evidence suggests that these all contain bridging hydrazine ligands, the cobalt and nickel complexes containing six coordinated metal atoms while the zinc and cadmium complexes are tetrahedral. 2,2,2-Trifluoroethylhydrazine (TFEH) in contrast, forms six coordinate complexes of the type MX₂(TFEH)₄ (M = Co, Zn, X = Br; M = Co, Ni, X = NCS; M = Ni, X = Cl) for which spectroscopic evidence points to unidentate coordination by the hydrazine. An X-ray crystal structure determination on NiCl₂(TFEH)₄ confirms that the hydrazine bonds to nickel through the NH₂ nitrogen only, in a tetragonal structure with axial chlorine atoms. One bis(TFEH) complex ZnBr₂(TFEH)₂ and one hexakis (TFEH) complex, NiBr₂(TFEH)₆, have also been isolated.     

Cationic complexes of chelated bis(η-cyclopentadienyl)titanium(IV) with halometallates of gallium(III), indium(III) and thallium(III)

Summary Eight complexes of the chelated bis(-cyclopenta-dienyl)titanium(IV) cation. [-Cp₂TiL][MX₄] (L = acetyl-acetone, M = Ga^III, In^III or Ti^III: X = Cl, Br or I) have been isolated from aqueous solution and characterised by elemental analyses and i.r. data. Their ionic nature has been confirmed by conductance measurements.     

Crystal structure of the 1∶1 clathrate of dichlorotetrakis(pyridine) cobalt(II) with chloroform

[CoPy₄Cl₂]·CHCl₃ (Py=pyridine, C₅H₅N) clathrate was first synthesized and studied by single crystal X-ray diffraction analysis at 150 K (KM-4 diffractometer, λMoK_α radiation, graphite monochromator, ω/2θ scan mode, θ_max=35°,5894 reflections, R=0.043). The crystals are monoclinic; the unit cell parameters at 150 K are: a=14.76(2), b=9.40(1), c=17.645(6) Å, β=92.18(5)⁰, Z=4, space group P2₁/c, d_calc=1.536 g/cm³. The structure is of molecular-island type and consists of asymmetric distorted octahedral complex molecules of trans-[CoPy₄Cl₂] (host) and CHCl₃ (guest). In addition to van der Waals contacts between the guest and host, shortened C?H...Cl and Cl...Cl distances have been found.