Crystal and molecular structure of dichloro(R(+)-N,N,N′,N′-tetramethyl-1,2-propylenediamine)cobalt(II)

The structure of the title complex [Co(R-Me₄pn)Cl₂] has been determined by single-crystal X-ray analysis and refined by least-squares methods based on diffractometer data (1224 counter intensities,R = 0.044). The blue crystals are orthorhombic, space groupP2₁2₁2₁, withZ = 4,a = 8.254(3),b = 10.926(4) andc = 13.584(5) Å. The cobalt(II) ion has a distorted tetrahedral coordination geometry with N-Co-N 87.8 ° and Cl-Co-Cl 118.5 °. The observed distortions are compared with those reported for analogous quasitetrahedral [M(II)(diamine)(dihalide)] complexes.     

Crystal and molecular structure of nitrito-bis(1,3-propanediamine) nickel(II) tetraphenylborate

The title compound is orthorhombic,M _r =590.2,P2₁2₁2₁ (No. 19),a=9.865(2),b=9.924(2),c=31.202(7) Å,V=3055(2) ų,Z=4,D _x =1.283 g cm^–3, (MoK );F(000)=1256; (MoK )=6.76 cm^–1, finalR=0.052 for 1441 reflections I2.5(I). The nitrite group is chelated via the two oxygen atoms; the two six-membered rings resulting from the coordination of the 1,3-propanediamine ligands to the nickel(II) atom are in the chair conformation. The Ni-N and Ni-O distances average 2.07(1) and 2.14(2) Å respectively. The two Ni-O distances are nearly equivalent.     

Crystal and molecular structure of bis(tetrathiafulvalene) bis(maleonitrile-1,2-dithiolato)nickelate(II)

The crystal and molecular structure of the title compound, C₂₀H₈N₄S₁₂Ni, is reported. Crystals are triclinic, space groupP¯1 (No. 2) withz=1 in a cell of dimensionsa=8;482(2),b=7.950(2),c=9.976(2) Å,=95.64(2),=98.60(2), and =87.65(2)°. The structure was solved by Fourier methods and refined by the method of least squares toR=0.033 for 2027 unique reflections. The Ni atom has an approximate square-planar configuration with Ni-S(1)=2.179(1), Ni-S(2)=2.175(1) Å, and the S(1)-Ni-S(2) bite angle of 91.89(4)°. The anions and the cations form a mixed stack (DAD-DAD-) along the diagonal of theab plane, showing the possibility of unusual electrical behavior.     

Crystal and molecular structure of 2:1 complex of 1,3-dimethyl violuric acid-mercury(II)

The complex (C₆H₆N₃O₄)₂Hg crystallizes in space groupP¯1, witha=16.635(2),b=11.765(2)c=9.288(2),=98.74(2),=102.99(2),=108.13(1)°,V=1634.3(6) ų andZ=4. The structure was solved by the heavy-atom method, and refined by full-matrix least squaresR andR _w values of 0.051 and 0.044, respectively, for 3108 uniquc reflections. The Hg(II) atom displays a highly distorted tetrahedral coordination geometry. It is bonded to two nitrogens and two oxygens of the two modified uracil base ligands in an unequalcis-bidentate manner. The ligand exists in the triketo form. The crystal structure is stabilized by C-HO interactions.     

Crystal and molecular structure of bis-tetraphenylarsonium-tris-(cis-1,2-dicyano-1,2-ethylenedithiolato)Fe(IV)

The crystal structure of bis-tetraphenylarsonium-tris-(cis-1,2-dicyano-1,2-ethylenedithiolato)Fe(IV), [(C₆H₅)₃As]₂Fe[S₂C₂(CN)₂]₃, has been determined using 3154 independent, non-zero reflexions collected by counter techniques. The substance crystallizes in the monoclinic system: space groupI2/a,a = 20·153(8),b = 13·411(5),c = 21·497(8) Å and = 95·28(8) °;D _m = 1·41(2),D _c = 1·43 g cm^–3 andZ = 4. The structure consists of Ph₄As⁺ cations in general positions and tris-(cis-1,2-dicyano-1,2-ethylenediothiolato)Fe(IV) anions on two-fold axes. Although the coordination around the arsenic atom is tetrahedral, the overall symmetry of the cation is 1 (C ₁), probably because the phenyl rings are rotated to accommodate the requirements of packing. The coordination of the six sulphur atoms about the iron atom is trigonal antiprismatic, approximating closely to an octahedron: for any pair oftrans sulphur atoms, the S-Fe-S angle is about 171 °.     

Crystal and molecular structure of tetrapyridyl-copper(II)-bis-nitrato-bis-pyridine

The crystal and molecular structure of a pyridine complex of anhydrous copper(II)nitrate is described. The structure has been solved by vector search methods and refined by least-squares methods to R₁=0.049 [I>2(I)]. The complex lies on a twofold axis parallel toa, and two solvent pyridine molecules lie on twofold axes parallel toc. The copper atom is coordinated by four pyridyl groups and two monodentate NO₃ groups. Crystal data: C₃₀H₃₀N₈O₆Cu, orthorhombic, space group Pnna(52),a=14.446(7),b=12.154(5),c=16.881(4) Å,V=2964(2) ų,Z=4.     

Crystal and molecular structure of dimethanolbis(salicylaldehydato)cobalt(II), C16H18CoO6

The structure of dimethanolbis(salicylaldehydato)cobalt(II) has been determined by three-dimensional X-ray diffraction methods. The crystals are monoclinic, space groupP2₁/c,a = 5.099(7),b = 19.446(9),c = 8.889(7) Å, = 111.85(10) °, andZ = 2. The structure consists of discrete centro-symmetric molecules of C₁₆H₁₈CoO₆ in which the oxygen atoms form a distorted octahedron about the cobalt atom, with cobalt-oxygen distances of 2.010(4), 2.076(4) Å (salicylaldehyde) and 2.115(4) Å (methanol). The molecules are linked together along thea-axis by intermolecular hydrogen bonds from the hydrogen atoms of the methanol groups to phenolic oxygen atoms of neighboring molecules. The final conventionalR-factor for 1232 observed reflections is 0.058.     

Crystal and molecular structure of a cobalt(II) complex with bis(benzimidazol-2-ylmethyl)-methylamine (L)

The reaction product of Co(II) chloride and the title ligand L, formulated as CoLCl₂·CH₃OH, was prepared and characterized by means of structural and spectroscopic measurements. The violet crystals are orthorhombic, (space groupP2₁2₁2₁) witha=8.093(2),b=14.883(3),c=16.831(3) Å, andZ=4. The structure consists of discrete molecules with pseudo-, noncrystallographic twofold symmetry in which the Co atom is coordinated in trigonal bipyramidal geometry by three nitrogen and two chlorine atoms. The ligand L is coordinated to the Co atom in afac mode and two chlorine atoms are incis-positions. The structure was confirmed by IR-spectra.     

Cobalt(II) and nickel(II) complexes ofN-protected amino acids. Crystal and molecular structure of bis (N-acetylglycinato)tetraaquocobalt(II)

Binary complexes of formula [M(II)(acgly)₂(H₂O)₄] (M(II)=Co(II), Ni(II), acgly=N-acetylglycinate ion) were synthesized, and for the Co(II) complex the crystal and molecular structure was determined. The crystals are monoclinic, space groupP2₁/c,a=4.838(1),b=10.785(2),c=14.340(6) Å,=96.96(2)°,Z=2. The structure was solved by the heavy-atom method and refined through full-matrix least-squares calculations toR=0.0394 for 1069 observed reflections. The coordination around the cobalt atom is slightly elongated octahedral arising from one carboxylate oxygen of each of the two centrosymmetrically related monodentateN-acetylglycinate anions and four water molecules.     

Crystal and molecular structure oftrans-dichlorobis(N-propylimidazole)palladium(II)

The crystal structure of Pd(N-PropIm)₂Cl₂ has been determined from X-ray data collected by counter methods. The compound crystallizes in the monoclinic space groupP2₁/n with four molecules per unit cell, the dimensions of which area=14.554(5),b=8.204(2),c=14.860(3) Å,=115.63(2)°. Full-matrix least-squares refinement gave a final R value of 0.0263 for 1913 independent observed reflections. The Pd atom is four-coordinated and is surrounded in atrans square planar fashion by two N atoms of the imidazole groups and by two Cl ions.     

Crystal and molecular structure oftrans-dichlorobis(oxazole)palladium(II)

The crystal and molecular structure oftrans-dichlorobis(oxazole)palladium-(II), Pd(C₃H₃ON)₂Cl₂, has been determined by single-crystal X-ray diffraction techniques using counter methods and has been refined by full-matrix least-squares procedures to a finalR index of 0.022. The complex crystallizes in the triclinic space groupP¯1 with unit cell dimensions ofa = 6.957(1),b = 7.506(1),c = 5.538(1) Å, = 109.22(1), = 91.37(1), and = 115.09(1) °, withZ = 1. The palladium(II) ion, located at an inversion center, is coordinated in a regular square-planar manner to two chloride ions at 2.293(1) Å and, at 2.016(2) Å, to the nitrogen atoms of two oxazole ligands. The planar oxazole rings are tilted 33 ° with respect to the PdN₂Cl₂ plane. Further verification of the presence of oxazole in the complex was obtained by high-resolution mass spectrometry. Crystals of Pd(C₃H₃ON)₂Cl₂ resulted irreproducibly from attempts to prepare single crystals of a previously reported dimeric palladium(II) disulfide complex by treating Pd(CH₃CN)₂Cl₂ with a slight excess of diphenyl disulfide in benzene in the atmosphere. The source of the oxazole is not understood.     

Crystal structure and vibrational spectra of polyamine-copper(II) complexes

The structures of [Cu(en)(H₂O)₂]SO₄ (I), [Cu(en)₂](NO₃)₂ (II) and [Cu(trien)I]I (III) have been determined by single crystal X-ray diffraction. ComplexI is monoclinic, space group C2/c, with unit cell parametera=7.232(1),b=11.725(2),c=9.768(1), =105.50(1)°, andZ=4. ComplexII is also monoclinic, space group P2₁/a, witha=7.978(2),b=9.982(4),c=8.218(3), =111.11(2)°, andZ=2. ComplexIII is orthorhombic, space group P2₁2₁2₁, witha=8.098(1),b=11.902(1),c=13.682(2), andZ=4. The structures were solved by direct methods and refined by full-matrix least-squares to finalR values of 0.031, 0.043 and 0.036 for complexesI, II, andIII, respectively. ComplexesI andII show an octahedral coordination geometry. ComplexIII shows a square pyramidal coordination geometry. ComplexI forms infinite monodimensional chains where the SO ₄ ^2– ions acts as a bridge between two neighboringen molecules. The vibrational spectra of these complexes agree well with their crystal structures. Structure and stability of seven other related Cu(II) complexes of (trien), (dien)₂, (en)₂ and (en) are inferred in this study.     

Synthesis of 1,2-dimethoxy-1,2-di(pyridin-2-yl)-1,2-ethanediol: Crystal and molecular structure determination

The compound, 2-hydroxy-[1,2-di(pyridin-2-yl)]ethane-1-one, 1, was isolated from the reaction of 2-pyridinecarboxaldehyde and 2-pyridinemethanol at 140°C without catalyst or solvent and characterized by¹H-NMR and IR spectral data. The compound 1 was treated with ethyl acetate to produce the 1,2-di(pyridin-2-yl)ethane-1,2-dione, 2. When 2 was dissolved in an excess of CH₃OH, crystals of 1,2-dimethoxy-1,2-di(pyridin-2-yl)-1,2-ethanediol, 3, were obtained. The molecular and crystal structure of 3 was determined by single crystal X-ray diffraction. The compound crystallizes in the monoclinic system belonging to the P2₁/n space group with a = 6.867(2) ?, b=9.546(4) ?, c=10.522(5) ?, α=90°, β=98.48(4)°, γ=90°. The asymmetric unit comprises two molecules of 3. Although the di-hemiketal was obtained in crystal form, it was found to be unstable, because its IR spectrum changed after a short time, indicating that it had been converted back to the original diketone, 2. The IR showed signals at 1713, and 1690 due to νC =O assigned to di-ketone group.     

Crystal and molecular structure of 1,2-difluoroethane and 1,2-diiodoethane

A single crystal of phase 1 of 1,2-difluoroethane was grown from the melt directly on an X-ray diffractometer close to the melting point of 169 K. It crystallizes in the monoclinic space group C2/c with lattice parameters a = 7.775(4), b = 4.4973(7), c = 9.024(3) Å, = 101.73(1)°, V = 308.9(2) ų, d _calc = 1.420 g cm^–3 for Z = 4. A second phase of 1,2-difluoroethane was obtained under similar conditions which crystallizes in the orthorhombic space group P2₁2₁2₁ with the unit cell parameters a = 8.0467(16), b = 4.5086(9), c = 8.279(2) Å,V = 300.36(11) ų, d _calc = 1.461 g cm^–3 for Z = 4. In both phases the 1,2-difluoroethane molecules adopt the gauche conformation with F–C–C–F torsion angles close to 68°. Crystals of 1,2-diiodoethane C₂H₄I₂ were grown from pentane at –30°C. A platelet single crystal of the size 0.35 × 0.25 × 0.03 mm was measured with Mo K-radiation at 153 K. 1,2-Diiodoethane crystallizes in the monoclinic space group P2₁/n with a unit cell of a = 4.6051(7), b = 12.939(2), c = 4.7318(7) Å, = 104.636(3)°, V = 272.79(7) ų, Z = 2, d _calc = 3.431 g cm^–3, (MoK) = 11.353 mm^–1. In the molecule the two neighboring iodine atoms are positioned anti. The shortest intermolecular contacts occur via iodine–iodine interactions resulting in layers of molecules in the crystal.     

Crystal and molecular structure of bis(aminomethylphosphonate)copper(II)

The crystal and molecular structure of bis(aminomethylphosphonate)-copper(II), C₂H₁₀N₂O₆P₂Cu, has been determined from MoK diffractometer data. The compound crystallizes in the monoclinic space groupP2₁/n witha =7.571(2),b = 4.943(1),c = 11.212(3) Å, = 105.84(2) °, andZ = 2. The structure was solved by the heavy-atom technique and refined by full-matrix least-squares methods toR = 0.041, using 1084 reflections for which ¦F _o¦ > 3.92 (¦F _o¦). In this complex, the Cu atom is square-planar coordinated by four O atoms from four phosphonic groups, and not by the amino group. The Cu-O bond lengths are 1.928(3) and 1.937(3) Å, and the phosphonic groups bridge adjacent Cu atoms in polymeric chains. The infrared spectrum of this complex is reported.     

Crystal and molecular structure of dibromobis(benzimidazole)copper(II)

The reaction of CuBr₂ with benzimidazole and HBr in aqueous solution leads to the formation of Cu(C₇H₆N₂)₂Br₂ as dark-brown, stable monoclinic crystals. Space groupP2₁/c witha=13.794(5),b=7.875(2),c=14.510(6) Å;=105.82(5)°;V _c =1516(5) ų;D _x =2.010(3) Mg m^–3. The structure was refined by a full-matrix least-squares procedure to giveR=R _w =0.045 for 1932 intensities above 3(I). The copper (II) ions are four coordinates in the form of a distorted flattened tetrahedron CuN₂Br₂, with the bond lengths Cu-Br(1)=2.402(1), Cu-Br(2)=2.446(1), Cu-N(1)=1.976(7), and Cu-N(11)=1.946(7) Å. The flattened angles are Br-Cu-Br=139.0(1) and N-Cu-N=154.6(3)°. The geometry of intermolecular and intramolecular hydrogen bonds is discussed.     

Crystal and molecular structure of bis[(1,2-dihapto-3,5-dimethyl-pyrazolido)-π-allylpalladium(II)]

The crystal and molecular structure of bis[(1,2-dihapto-3,5-dimethylpyrazolido)--allylpalladium(II)], C₁₆H₂₄N₄Pd₂, has been determined by X-ray diffraction techniques. The crystals are monoclinic,P2₁/c (No. 14), witha = 8.752(1),b = 18.932(2),c = 11.780(3) Å, and = 109.78(1) °. The observed crystal density (1.746 g cm^–3) agrees well with that calculated on the basis of four molecules per unit cell (1.754 g cm^–3). The structure has been refined by full-matrix least-squares techniques to a finalR ₁ value of 0.045 (R ₂ = 0.056) for 2974 unique reflections withI _net7 counts sec^–1. The Pd₂N₄ ring is in a boat conformation in which the two palladium atoms are 1.113 and 1.064 Å out of the plane defined by the four nitrogen atoms. The Pd-C bond distances to the terminal atoms of the -allyl groups (2.12 Å) are longer than those to the central carbon atoms (2.06 Å). The molecule possesses approximatemm2 (C _2v ) symmetry.     

Crystal and molecular structure of nickel(II) dicyanothiosemicarbazide monohydrate

The structure of the title compound (Ni(CN)₂(CH₅N₃S)·H₂O) has been determined, from X-ray diffractometer data, by the heavy-atom method and refined by least-squares. The finalR-values, based on 3109 observed reflections, areR=0.035 andR _w =0.039. The complex has square-planar geometry with two adjacent cyano carbon atoms (Ni-C, 1.838(2) Å and 1.862(2) Å)and thiosemicarbazide sulfur and nitrogen atoms (Ni-S, 2.169(1) Å and Ni-N, 1.923(2) Å). The water molecule does not enter the inner coordination sphere of the nickel atom; however, it plays a very important role in the crystal structure. Water is coordinated by hydrogen bonds to four adjacent complex units.