Zur Struktur eines ungewöhnlichen Tetramers des Lithiumphenolats: [C6H5OLi · C4H8O]4 · C6H5OH

The Structure of an unusual Tetramere of Lithium Phenoxide: [C₆H₅OLi · C₄H₈O]₄ · C₆H₅OH Single crystals of lithium phenoxide have been obtained from THF. In the structure (P 2₁/n, Z = 4, a = 11.69 Å, b = 21.15 Å, c = 18.55 Å, β = 91.11°) four lithium atoms and four phenoxide oxygen atoms are cubically arranged. Further, each lithium atom coordinates the oxygen atom of a tetrahydrofuran molecule. The ideal cubeform structure is disturbed by one phenol molecule which is coordinated in addition to four phenoxide and four THF molecules. Hence, one edge of the cube (Li4? O4) is substituted by the coordination of the phenol oxygen atom O5 with Li4 and hydrogen bonding between O4 and the hydroxy group of phenol. Van der Waals forces are the only interaction between these complexes.     

A new binuclear germanium(IV) and copper(II) complex with 1,3-diamino-2-propanoltetraacetic acid: Crystal and molecular structure of [(H2O)(OH)Ge(μ-Hpdta)Cu(H2O)] · 3H2O

A heteronuclear germanium(IV) and copper(II) complex with 1,3-diamino-2-propanoltetraacetic acid (H₅Hpdta) has been synthesized for the first time. The compound has been characterized by elemental analysis, X-ray diffraction, thermogravimetry, and IR spectroscopy. The structure of the complex [(H₂O)(OH)Ge(μ-Hpdta)Cu(H₂O)] · 3H₂O (I) has been determined by single-crystal X-ray diffraction. The crystals of I are monoclinic, a = 1 5.327(4) Å, b = 11.626(3) Å, c =21.058(3) Å, β = 96.35(2)°, V = 3729.2(2) ų, Z = 8, space group C2/c, R1 = 0.0551 on 3090 reflections with I > 2σ(I). The structural units of the crystal of I are binuclear complex molecules [(H₂O)(OH)Ge(μ-Hpdta)Cu(H₂O)] and crystal water molecules. The germanium and copper atoms are linked by the bridging oxygen atom of the deprotonated isopropanol group of the Hpdta^5? ligand (Ge-O, 1.843(3) Å; Cu-O, 2.221(3) Å). The coordination spheres of the Ge and Cu atoms contain each one nitrogen atom (Ge-N, 2.090(4) Å; Cu-N, 2.000(4) Å) and two carboxyl oxygen atoms from four acetate arms of the heptadentate Hpdta^5? ligand (av. Ge-O, 1.909(3) Å; Cu-O, 1.948(3) Å). The coordination polyhedron of the Ge atom is completed to a distorted octahedron by the oxygen atoms of the terminal hydroxy group (Ge-O, 1.786(3) Å) and a water molecule (Ge-O, 1.904(3)Å). The coordination polyhedron of the copper atom is completed to a prolate tetragonal pyramid (4 + 1) by the oxygen atom of a water molecule in the equatorial position (Cu-O, 1.955(4) Å) and the bridging O(11) atom (Hpdta^5?) in the apical position. Binuclear molecules are linked pairwise in a head-to-head manner via double Cu-O(2) bridges to form the centrosymmetric tetranuclear supramolecule {[(H₂O)(OH)Ge(μ-Hpdta)Cu(H₂O)]}₂. The coordination of the Cu atom is completed by the weak Cu-O(2A) contact (3.303 Å) to an asymmetrically elongated tetragonal bipyramid (4 + 1 +1). In the crystal, the complex molecules and crystal water molecules are combined by a system of hydrogen bonds into a three-dimensional framework.     

Synthesis of ruthenium-palladium and ruthenium-rhodium complexes linked by pyrazolate groups and chlorine atoms. Crystal structure of [(p-cymene)ClRu(μ-Cl)(μ-pz)Pd(C8H11)]

The preparation of new heterobinuclear compounds of formula [(p-cymene)RuX₂(Pz)ML₂] (M = Pd, X = Cl, L₂ = C₃H₅, C₄H₇ or C₈H₁₁; Pz = pz ¹; M = Rh, X = Cl or I, L₂ = 5,6,7,8-tetrafluoro-1,4-dihydro-1,4-ethenonaphthalene, tfb, or bicyclo[2.2.1]heptadiene, nbd; Pz = pz or Mepz) is reported. One of the complexes, [(p-cymene)ClRu(μ-Cl)(μ-pz)Pd(C₈H₁₁)], has been characterized by single-crystal X-ray diffraction. The crystals are monoclinic, space group P2₁/c, with a 14.0044(10), b 14.9641(10), c 11.0456(5) Å, β 103.191(5)° and Z = 4. The structure has been refined to R = 0.064 for the 2850 observed reflexions with I ρ 3σ(I). The coordination of the Pd atom to the C₈H₁₁ ring system involves only three C atoms constituting a η³-allyl group, at 2.147(17), 2.101(15) and 2.119(17) Å from the Pd atom. The Ru-Pd distance is 3.516(1) Å, the two atoms being bridged by a chlorine atom and a pyrazolate group; the other chlorine atom is terminal.     

Crystal and molecular structures of triaquabis(5-nitro-2-acetamidobenzoato)copper(II) dihydrate

A new copper(II) complex [Cu(5-NO₂-2-CH₃CONHC₆H₃COO)₂(H₂O)₃] · 2H₂O was synthesized by the reaction of sodium 5-nitro-5-acetamidobenzoate with CuSO₄ · 5H₂O (2: 1), and its structure was determined by X-ray diffraction. Crystals are monoclinic: a = 11.7146(7) Å, b = 16.8463(10) Å, c = 13.2408(9) Å, β = 113.896(5)°, Z = 4, ρ_calc = 1.668 g/cm³, space group P2₁/c, R = 0.0338. In the monomer complex, the copper atom has an elongated square-pyramidal coordination (4 + 1); the coordination sphere is formed by two oxygen atoms of the carboxylate groups of two monodentate organic ligands and the three oxygen atoms O(w) of the water molecules (the O(3w) atom is in the axial position). In the structure, the complex molecules are linked by hydrogen bonds involving two uncoordinated water molecules.     

Synthesis and crystal structure of Cu(I) π-complexes with N-allyl-5-amino-1-phenyl-1H-1,2,3-triazole-4-carboxamide [Cu(C12H13N5O)(NO3)] · 0.5H2O and [Cu(C12H13N5O)(CF3COOH)]

Copper(I) ??-complexes of the compositions [Cu(C₁₂H₁₃N₅O)(NO₃)] · 0.5H₂O (1) and [Cu(C₁₂H₁₃N₅O)(CF₃COO)] (2) (C₁₂H₁₃N₅O is N-allyl-5-amino-1-phenyl-1H-1,2,3-triazole-4-carboxamide) were obtained by alternating-current electrochemical synthesis, and their crystal structures were studied by X-ray crystallography. Crystals of the compounds are monoclinic, space group C2/c with the unit cell parameters a = 21.3976(15) ?, b = 8.0335(4) ?, c = 18.6027(13) ?, ?? = 114.422(2)°, V = 2911.6(3) ?³, Z = 8 for 1; and a = 18.3578(18) ?, b = 9.8700(10) ?, c = 20.9094(18) ?, ?? = 106.883(3)°, V = 3625.3(6) ?³, Z = 8 for 2. In both structures, N-allyl-5-amino-1-phenyl-1H-1,2,3-triazole-4-carboxamide acts as a bridging tridentate chelating ligand and forms with copper(I) atoms infinite chains containing [CuC₄NO] seven-membered rings. The chains are linked to form a three-dimensional framework due to hydrogen bonds (N)H??O, which involve nitrogen atoms of amino and amide groups of the ligand. The coordination sphere of Cu(I) atoms consists of olefin bond of the allyl C=C group, O atom of the carbonyl group, N(3) atom of the triazole nucleus of the organic ligand, and an oxygen atom of nitrate (compound 1) or trifluoroacetate (compound 2) anion, respectively.     

A novel copper(II) complex with schiff base derived from o-vanillin and L-methionine: Syntheses and crystal structures

A new Schiff base copper(II) complex, {[CuL(H₂O)₂][CuL(H₂O)]₃ · 4H₂O · C₃H₇NO} _n (H₂L = (Z)-2-(2-hydroxy-3-methoxybenzylideneamino)-4-(methylthio)butanoic acid), was synthesized and characterized by IR, UV, and X-ray diffraction single-crystal analysis. The crystal belongs to the triclinic crystal system, space group with cell parameters a = 5.2027(5) Å, b = 16.6916(16) Å, c = 20.237(2) Å, α = 88.895(10)°, β = 84.127(1)°, γ = 83.577(10)°, V = 1737.2(3) ų, Z = 1, F(000) = 848, S = 1.042, ρ_calcd = 1.561 g cm^?3, μ = 1.411 mm^?1, the final R ₁ = 0.0760 and wR ₂ = 0.2318 for 6030 observed reflections (I > 2σ(I)). The crystal structure of the complex contains two independent units with different coordination environments. In independent unit 1, the Cu(1) is five-coordinated by one nitrogen atom and two oxygen atoms from the Schiff base ligand and two oxygen atoms from two water molecules to form a distorted square pyramid geometry. On the other hand, in independent unit 2, the Cu(2) is five-coordinated and possesses a slightly distorted square-pyramidal coordination geometry, defined by one nitrogen atom, one hydroxyl oxygen atom, two carboxylate oxygen atoms in two different ligands, and one oxygen atom of the water molecule. The complex forms a one-dimensional chain polymer in the xy plane through carboxyl oxygen atoms in the Schiff base ligands.     

Molecular and crystal structure of bis(1.10-phenanthroline)copper(I) (5-fluorouracil-1)-yl-acetate 3.25 hydrate

In the title compound, (Phen)₂Cu^I(C₆H₄FN₂O₄) · 3.25H₂O (Phen is 1,10-phenanthroline and C₆H₄FN₂O₄ is (5-fluorouracil-1)-yl-acetate), each Cu⁺ ion is five-coordinated by four basal N atoms and one oxygen atom, and the coordination geometry around each Cu⁺ ion is an irregular square pyramid. The crystals are orthorhombic, space group Pnma, with a = 13.080 (3), b = 16.023(4), c = 130.422(8) Å.     

Crystal structure of a Mn(II) complex with isatin-hydrazone-S-benzyldithiocarbazate

The reaction of Mn(OAc)₂·4H₂O with isatin-hydrazone-S-benzyldithiocarbazate (HIsa-SBn) results in the formation of a bis-ligand complex [Mn(Isa-SBn)₂]·2DMF. Its single crystal is obtained and the structure is determined by X-ray diffraction. It belongs to a monoclinic space group C2/c with the cell parameters: a = 23.290(4) Å, b = 11.4980(18) Å, c = 18.483(5) Å, V = 4087.6(14) ų. The Mn(II) atom is six-coordinated with two amide O atoms, two azomethine N atoms, and two thiolate S atoms, resulting in a distorted octahedral geometry.     

The coordination properties of aminobenzoate ligands in complexes with alkali metals

The crystal structures of sodium 4-amino-2-hydroxybenzoate dihydrate [NaL·2H₂O, L?= C₆H₃(NH₂)(OH)COO] and potassium 2-aminobenzoate monohydrate [KL*·H₂O, L*?=?C₆H₄(NH₂)COO] were determined by X-ray diffraction methods. The compound NaL·2H₂O crystallizes in the monoclinic system, space group P2₁/c with a?=?8.820(2), b?=?14.632(3), c?=?6.948(2)?Å, β?=?97.88(3)°. The structure consists of sodium ion pairs joined together by tridentate 4-amino-2-hydroxybenzoate moieties creating a polymeric chain. In the metal centres, two water molecules bridge the sodium atoms. Five oxygen atoms and one nitrogen atom form a distorted octahedral environment. The compound KL*·H₂O crystallizes in the monoclinic system, space group P2₁/c with a?=?14.684(3), b?=?7.618(2), c?=?7.512(2)?Å, β?=?96.95(3)°. The structure consists of octacoordinated potassium atoms bonded with three water molecules and five carboxylate oxygen atoms. Water molecules appear as bridging ligands. The 2-aminobenzoate ligand acts as a pentadentate ligand with the molecular network stabilized by hydrogen bonds. Among the polymeric chains in both structures appear noncovalent interactions of type N?H···X.     

Syntheses of (C_5H_9C_5H_4)_2LnCl(THF)_n (Ln=Nd, Sm, Er, Yb) and crystal structure of [(C_5H_9C_5H_4)_2-LnCl(THF)_n]_2(Ln=Sm, n=1; Ln=Er, n=0)

Reactions of lanthanoid trichlorides with sodium cyclopentylcyclopentadienyl in THFafford bis(cyclopentylcyclopentadienyl) lanthanoid chloride complexes (C_5H_9C_5H_4)_2LnCl(THF)_n (Ln=Nd, Sm, n=1; Ln= Er, Yb, n= 0). The compound [CP'_2SmCl(THF)]_2 (2) (Cp' =cyclopentylcy-clopentadienyl) crystallizes from mixed solvent of hexane and THF in monoclinic space group P_2_1/cwith a = 11.583 (3), b = 23.019(6), c = 8.227 (2), β= 90.26 (2)°, V= 2194 (1)~3, D_c= 1.59 g/cm~3.μ= 28.6 cm~(-1), F(000) = 1060, Z= 2 (dimers). Its crystal molecule is a dimer with a crystallographicsymmetry center. The central metal atom Sm is coordinated to two Cp' rings, two bridging chlorineatoms and one THF forming a distorted trigonal bipyramid. The crystal of [Cp'_2ErCl]_2 (3) belongs tothe triclinic space group P with a = 11.264 (2), b= 13.296(5), c = 14.296(6), a = 96.99 (3), β=112.47(2), γ= 102.78(2)°, V= 1865(1)~3, D_c= 1.67 g /cm~3, μ= 48.0 cm~(-1), F(000) = 924, Z = 2 (dimers).The molecule is a dimer consisting of two Cp'_2 ErCl species bridged by two Cl atoms. The centralmetal atom Er is coordinated to two Cp' rings and two bridging chlorine atoms forming a pseudo-tetrahedron. All these complexes are soluble in THF, DME, Et_2O, toluene and hexane.     

Synthesis and characterization of heteronuclear germanium(IV) and lanthanum(III) (chromium(III)) complexes with 1,3-diamino-2-propanoltetraacetic acid: Crystal and molecular structure of [Ge(OH)(μ-Hpdta)(μ-OH)La(H2O)4] · H2O

Two heteronuclear germanium(IV) and lanthanum(III) (chromium(III)) complexes with 1,3-diamino-2-propanoltetraacetic acid (H₅Hpdta) have been synthesized. The compounds have been characterized by elemental analysis and X-ray powder diffraction data. The structure of [Ge(OH)(??-Hpdta)(??-OH)La(H₂O)₄] · H₂O (I) has been determined by X-ray crystallography. The crystals are monoclinic, a = 9.3805(3) ?, b = 10.3023(4) ?, c = 21.6527(6) ?, ?? = 94.829(2)°, V = 2085.10(12) ?³, Z = 4, space group P2₁/n, R1 = 0.0294 based on 5480 reflections with I > 2??(I). Compound I is composed of binuclear [Ge(OH)(??-Hpdta)(??-OH)La(H₂O)₄] molecules and crystal water molecules. In the dimeric molecule, the germanium and lanthanum atoms are linked by the bridging oxygen atom of the hydroxo ligand and the oxygen atom of the deprotonated isopropanol group of Hpdta^5?. The coordination spheres of germanium and lanthanum each contains one nitrogen atom and two carboxyl oxygen atoms of the four acetate arms of the heptadentate Hpdta^5? ligand. The Ge coordination polyhedron is completed to a distorted octahedron by the oxygen atom of the terminal hydroxo group, and the lanthanum coordination polyhedron is completed to a nine-vertex polyhedron by the oxygen atoms of four water molecules. In crystal, the complex molecules and crystal water molecules are combined by a system of hydrogen bonds.     

The formation and molecular structure of (η5-C5H5)3Sm · OC4H8

Reaction of 1/2 mole ratio of (η⁵-C₅H₅)SmCl₂ ·3THF and NaCCCH₂OCH₂CHCH₂ in THF solution resulted in the formation of (η⁵-C₅H₅)Sm·OC₄H₈; the complex crystallizes in monoclinic space group P2₁/n with unit cell constants a = 8.254(5), b = 24.63(1), c = 8.339(3) Å, β = 101.33(5)° and D_c = 1.67 g/cm³ for Z = 4. Refinement has led to a final R value of 0.041 based on 2106 independent observed reflections. The THF molecule is coordinated to the samarium atom at a SmO distance of 2.522(6) Å. The SmC(cyclopentadienyl) bond lengths range from 2.70(1) to 2.80(1) Å and average 2.742(1) Å. A comparison of some significant structural parameters along the isostructural series (η⁵-C₅H₅)₃Ln·THF (LnLa, Pr, Nd, Gd, Dy, Lu and Sm) with the ionic radii of Ln³⁺ was made.     

Fulvene—platinum complexes: x-ray crystal structure of [Pt(η2-C5H4CPh2)(PPh3)2]

Bis(cycloocta-1,5-diene)platinum reacts with 2,3,4,5-tetraphenylfulvene to afford the complex [Pt(η²-CH₂C₅Ph₄)(cod)] (cod  C₈H₁₂) in which the metal atom is coordinated to the exo-cyclic double bond of the fulvene. Related compounds [Pt(η²-CH₂C₅Ph₄L₂] (L  PPh₃, PMePh₂, PMe₂Ph, AsPh₃ or CNBu^t have also been prepared and characterised. Reaction of the complexes [Pt(C₂H₄)₂(L)] (L  P(cyclo-C₆H₁₁)₃, PPh₃ or AsPh₃) with 2,3,4,5-tetraphenylfulvene yields the compounds [Pt(C₂H₄)(η²-CH₂C₅PH₄)(L)]. NMR data for the new species are reported and discussed. 6,6-Diphenylfulvene reacts with [Pt(cod)₂] and PPh₃ ($\text{1}\text{2}$ mol ratio) to give the complex [Pt(η²-C₅H₄CPh₂)-(PPh₃)₂] in which the metal atom is bonded to carbon atoms C(2) and C(3) of the fulvene ring. This was established by an X-ray diffraction study. Crystals are monoclinic, space group P2₁/n, with Z  4 in a unit cell of dimensions a  13.761(4), b  21.653(13), c  17.395(6) Å, β,  104.46(2)°. The structure has been solved and refined to R  0.064 (R′  0.064) for 3139 independent diffracted intensifies measured at room temperature. The platinum atom is in a trigonal environment formed by the two ligated phosphorus atoms and the CC bond of the fulvene which is elongated to 1.52(3) Å. The c₅ fulvene ring is planar, and makes an angle of 108° with the coordination plane around the platinum. In this plane the metal atom is slightly asymmetrically bonded with PtC 2.15(2) and 2.24(2) Å, and PtP 2.280(6) and 2.301(6) Å.     

Syntheses and Crystal Structures of Lanthanide Chloride Complexes with Diglyme

Reactions of [LnCl₃(DME)₂] (Ln = Nd, Sm, Ho, Lu; DME = dimethoxyethane) and diglyme (diglyme = diethylen glycol dimethyl ether) in THF resulted in polymeric [LnCl₃(diglyme)]_n (Ln = Nd ( 1 ), Sm ( 2 )) or mononuclear complexes [LnCl₃(diglyme)(THF)] (Ln = Ho ( 3 ), Lu ( 4 )). Neodymium and samarium atoms in 1 and 2 are eight‐coordinated by three oxygen atoms from diglyme, one terminal and four bridging chloride ions. Holmium and lutetium atoms in 3 and 4 are seven‐coordinated by three oxygen atoms from diglyme, three chloride ions and one oxygen atom from THF. [ErCl₃(diglyme)(H₂O)] ( 5 ) resulted from the reaction of ErCl₃·6H₂O, (CH₃)₃SiCl and diglyme in THF. The molecular structures of 3 , 4 and 5 are similar, with either a molecule of THF coordinated to the lanthanide atom in 3 and 4 or with a molecule of water coordinated in 5 .     

Crystal structure of potassium 2-thiobarbiturate

The crystal and molecular structure of potassium thiobarbiturate C₄H₃KN₂O₂S (C₄H₄N₂O₂S-2-thiobarbituric acid, H₂TBA) is determined. Crystallographic data for KHTBA are as follows: a = 11.2317(17) Å, b = 3.8687(6) Å, c = 14.557(2) Å, β = 97.448(4)°, V = 627.18(17) ų, space group P2/c, Z = 4. Each potassium ion is linked with four oxygen atoms and two S atoms forming a distorted octahedron. N-H…O and C-H…S hydrogen bonds form a branched three-dimensional network. The structure is also stabilized by the π-π interaction of heterocyclic HTBA^? ions.     

Ein fünffach koordinierter ionischer zirkonium(IV)-komplex mit der (π-C5H5)2ZrIV-Baueinheit: [(π-C5H5)2Zr(H2O)3]2+(CF3SO3−)2·THF

The ionic complex [(π-C₅H₅)₂Zr(H₂O)₃]²⁺(CF₃SO₃^?)₂·THF, which corresponds to the 18-electron rule, is formed in the reaction of (π-C₅H₅)₂Zr(CF₃SO₃)₂(THF) with H₂O in tetrahydrofuran. It crystallizes in the hexagonal space group P6₃ with Z = 6 and unit cell dimensions at ? 100°C of a 21.945(5) and c 8.711(3) Å. The geometry of the (π-C₅H₅)₂Zr moiety (length of the vectors between Zr and the C₅ ring centroids: 2.210 and 2.193 Å; angle between these vectors: 129.0°; angle between the C₅ ring normals: 128.3°) agrees with that of neutral, four-coordinate (π-C₅H₅)₂ZrX₂ compounds. The three H₂O ligands lie in the plane that bisects the angle between the C₅ ring planes. The ZrO distances are 2.239(7), 2.195(7), and 2.261(7) Å. The CF₃SO₃^? anions and the THF molecule of crystallization are packed around the complex cation in such a way that their oxygen atoms point towards the H₂O ligands. The CF₃ sides of the anion, on the other hand, are clustered together so as to produce hydrophobic domains in the crystal structure.     

Electronic properties and crystal structure of aqua (mepirizole-oxalato)copper(II)monohydrate: [Cu(C11H14N4O2)C2O4·H2O]H2O

A Cu(ll) complex with mepirizole: 4-methoxy-2-(5-methoxy-3-methyl-pyrazoll-yl)-6-methylpyrimidine (L) and oxalate as ligands with the formula [CuL(C₂O₄)(H₂O)]·H₂O has been synthesized. The crystal structure has been determined by X-ray diffraction analysis: monoclinic, space group P2₁/n, Z = 4, a = 7.707(1), b = 14.951(3), c = 14.986(2) Å,β = 92.40(2)°, V = 1725.2(8) ų, D_m = 1.61(1) g cm⁻³, D_c = 1.62 g cm⁻³, R = 0.032 and R_w = 0.035 for 2016 observed reflections. The CuN₂O₂O′chromophore can be described as square pyramidal strongly distorted towards trigonal bipyramidal. The basal coordination positions are occupied by the two oxygen atoms of the bidentate oxalate group, the coordinated water molecule and one nitrogen atom of the bidentate mepirizole group; the other coordinated nitrogen atom occupies the apical position. Magnetic moment, IR, electronic reflectance and ESR spectra are interpreted in accordance with the proposed stereochemistry.     

Metallorganische verbindungen der lanthanoide: LXXXV. Synthese und strukturaufklärung neuer cyclooctatetraenyl-cyclopentadienyl-sandwich-komplexe der seltenen erden

The mixed sandwich complexes [(C₈H₈)Ln(C₅Me₄Et)(THF)_x] (Ln = Y 1, La 2, Nd 3, Sm 4, Gd 5, Tm 6, Lu 7), [(C₈H₈)Ln{C₅H₂(SiMe₃)₃}(THF)_x (Ln = Pr 8, Dy 9) and [(C₈H₈)Pr(C₅Ph₅)] (10), have been prepared by the metathetic reaction of [(C₈H₈)Ln(μ-Cl)-(THF)_n]₂ with NaC₅Me₄Et, LiC₅H₂(SiMe₃)₃ and NaC₅Ph₅ in THF. The 1:2 reaction of 7 with acetylacetone results in displacement of the (C₈H₈)-ligand to generate the new complex [(C₅Me₄Et)Ln(acac)₂] (acac = [CH₃C(O)CHC(O)CH₃]⁻) (11). The molecular structures of 7 (monoclinic space group P2₁/c with a = 990.4(5) pm, b = 1228.2(5) pm, c = 2757.5(16) pm, β = 93.92(4)°, V = 3346(3)·10⁻³⁰ m³ and Z = 8) and 11 (triclinic space group P1̄ with a = 957.3(3) pm, b = 1064.5(2) pm, c = 1068.3(2) pm, α = 94.19(12)°, β = 96.37(17)°, γ = 96.71(16)°, V = 1070.3(4)·10⁻³⁰ m³ and Z = 2) have been determined by X-ray diffraction.     

Synthese und Kristallstruktur des Nitrido-Oxalato-Osmats PPh4{Na(15-Krone-5)[OsNCl3(C2O4)]}

Synthesis and Crystal Structure of the Nitrido Oxalato Osmate PPh₄{Na(15-Crown-5)[OsNCl₃(C₂O₄)]} The title compound has been prepared by slow reaction of PPh₄[OsNCl₄] with sodium oxalate in boiling dichloromethane in the presence of 15-crown-5, forming violet crystals, which were characterized by an X-ray structure determination. Space group P2₁/c, Z = 4, 4 769 observed unique reflections, R = 0.035. Lattice dimensions at –80°C: a = 1 931.4, b = 1 178.7, c = 1 764.1 pm, β = 99.39°. The structure consists of PPh₄⁺ ions and ion pairs {Na(15-crown-5)[OsNCl₃(C₂O₄)]}^?, in which the osmium atom is distortedly octahedrally coordinated by the nitrido ligand, by three chlorine atoms, and by two oxygen atoms of the oxalato group. The remaining oxygen atoms of the oxalato ligand are coordinated to the sodium atom, which, together with the five oxygen atoms of the crown ether molecule, gets coordination number seven.     

The crystal structure of tetrachloro(diethylphthalate)titanium(IV)

The crystal structure of [C₆H₄(OCOC₂H₅)₂TiCl₄], which in the presence of activators is a good catalyst for olefin polymerization, has been determined by X-ray diffraction methods and refined by full-matrix least-squares techniques to R = 0.045 for 2000 independent non-zero reflexions. Crystals are orthorhombic, space group Pnma, with four molecules in a cell of dimensions: a 11.45(1), b 14.07(1), c 10.56(1) Å. The structure consists of discrete molecules possessing crystallographic m (C_s) point symmetry. The Ti atoms are octahedrally coordinated by four chlorine atoms and two carbonyl oxygen atoms of diethylphthalate. The chelating ligand atoms together with the titanium atom form a seven-membered ring with the Cl and Ti atoms located above the benzene ring.