Gold-acetylide chemistry: the structure of the complex [Au2(μ-dppm) (C≡C—CMe3)2]

1995 ◽  
Vol 73 (1) ◽  
pp. 6-11 ◽  
Author(s):  
Nicholas C. Payne ◽  
Ravindranath Ramachandran ◽  
Richard J. Puddephatt
Keyword(s):  
Spectroscopic Properties ◽  
Molecular Structures ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
X Ray ◽  
X Ray Crystallography ◽  
Crystal And Molecular Structures ◽  
Cell Dimensions ◽  
Counter Data ◽  
Gold Acetylide

The complex [Au2(μ-dppm)(C≡Ct-Bu)2], 1, dppm=Ph2PCH2PPh2, is formed by reaction of [AuC≡Ct-Bu] with dppm. Compound 1, as an acetone solvate, crystallizes in the monoclinic space group P21/c with cell dimensions a = 14.047(1), b = 16.124(1), c = 17.140(3) Å, β = 103.17(2)° and four formula units per cell. The crystal and molecular structures of this salt were solved by X-ray diffraction techniques using 2634 counter data with I > 2σ(I). Refinement of 278 variables by full-matrix least squares converged at an agreement factor R = 0.023. Thermolysis of complex 1 in refluxing toluene led to intermolecular elimination of t-BuC≡CH, by combination of a t-BuC≡C ligand of one molecule of 1 with a proton from the CH2P2 group of a second, and formation of the stable tetragold(I) complex [Au4(μ3-Ph2PCHPPh2)(μ-dppm)(C≡Ct-Bu)3], 2, which was characterized by its spectroscopic properties. Keywords: acetylide complexes, gold complexes, X-ray crystallography, nmr spectroscopy, bis(diphenylphosphino)methane.

The Crystal and Molecular Structure of Pentane-2,4-dionato-(2,3,5,6-tetrahepto-2,3-dicarbomethoxo[2.2.1]bicycloheptadiene)rhodium(I), Rh(C5H7O2) (C7H6(CO2CH3)2)

1975 ◽  
Vol 53 (18) ◽  
pp. 2707-2713 ◽  
Author(s):  
Debbie Allen ◽  
Colin James Lyne Lock ◽  
Graham Turner ◽  
John Powell
Keyword(s):  
Crystal And Molecular Structure ◽  
Molecular Structures ◽  
Monoclinic Space Group ◽  
Intensity Data ◽  
X Ray Diffraction ◽  
Full Matrix ◽  
X Ray ◽  
Crystal And Molecular Structures ◽  
Square Planar ◽  
Rhodium Atom

The crystal and molecular structures of pentane-2,4-dionato-(2,3,5,6-tetrahapto-2,3-dicarbomethoxo[2.2.1]bicycloheptadienerhodium(I), Rh(C5H7O2)(C7H6(CO2CH3)2), have been measured by single crystal X-ray diffraction. The orange crystals are monoclinic, space group P21/c, Z = 4, a = 9.245(4), b = 9.003(4), c = 21.680(15) Å, β = 113.41(5)°. The calculated and observed densities are 1.645 and 1.642(5) respectively. Intensity data were collected on a Syntex [Formula: see text] diffractometer and a full matrix least squares refinement on 3010 observed reflections leads to a conventional R = 0.0660. The structure can be considered as a roughly square planar arrangement of ligands around the rhodium atom composed of two β-ketoenolate oxygen atoms (Rh—O, 2.037(5) and 2.025(5) Å ) and the centers of the two ethylenic groups. The Rh—C distances for the olefin group attached to the two carbomethoxo groups, 2.117(8), 2.108(8) Å, appear to be slightly larger than those for the other olefinic group, 2.087(7), 2.082(6), and the corresponding C=C distances of 1.375(10) and 1.410(9) Å are different at the 95% confidence level.

Metal-selenolate chemistry: stereochemistry of adamantane-type clusters of formula [(μ-SePh)6(MSePh)4]2− (M = Zn and Cd)

1992 ◽  
Vol 70 (3) ◽  
pp. 792-801 ◽  
Author(s):  
Jagadese J. Vittal ◽  
Philip A. W. Dean ◽  
Nicholas C. Payne
Keyword(s):  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Bridging Ligands ◽  
Triclinic Space Group ◽  
Space Group ◽  
X Ray ◽  
Space Groups ◽  
X Ray Crystallography ◽  
Cell Dimensions ◽  
Minimum Number

The structures of three tetramethylammonium salts containing anions of formula [(μ-SePh)6(MSePh)4]2− (M = Zn and Cd) were determined by single crystal X-ray diffraction techniques. The Zn salt crystallizes in different space groups depending upon the solvent combination used in the synthesis. Thus crystals of (Me4N)2[Zn4(SePh)10], 1, grown from a mixture of methanol, acetonitrile, and acetone are triclinic, space group [Formula: see text] with cell dimensions a = 13.214(2), b = 23.859(2), c = 13.072(1) Å, α = 91.134(8), β = 113.350(8), γ = 79.865(9)°, and Z = 2. In the absence of acetone, a solvated crystal (Me4N)2[Zn4(SePh)10]•CH3CN, 2, is formed, which belongs to the monoclinic space group P21/n with a = 14.248(1), b = 39.722(2), c = 13.408(1) Å, β = 97.132(5)°, and Z = 4. The Cd salt (Me4N)2[Cd4(SePh)10], 3, crystallizes in the monoclinic space group P21/c, with a = 20.830(2), b = 14.282(1), c = 25.872(1) Å, β = 99.626(6)°, and Z = 4. These three salts are the first examples of homoleptic, tetranuclear selenolatometal(II) anions with (μ-Se)6M4 cages of adamantane-type stereochemistry. In each case the phenyl substituents of the bridging ligands adopt the configuration [aae, aae, aee, aee], which has the minimum number of two 1,3-axial–axial non-bonding substituent interactions. Keywords: selenolate complexes, synthesis, X-ray crystallography, isomerism, adamantane stereochemistry.

Crystal structures of 1-(m-nitrophenyl)-2,2-dicarboethoxy-3-phenyl-pyrrolidin-5-one (C22H22N2O7) (I) and 1-(p-chlorophenyl)-2,2-dicarboethoxy-3-phenyl-pyrrolidin-5-one (C22H22NO5Cl) (II)

1989 ◽  
Vol 189 (3-4) ◽  
Author(s):  
G. D. Nigam ◽  
G. Mattern ◽  
R. Fröhlich
Keyword(s):  
Crystal Structures ◽  
Molecular Structures ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Crystal And Molecular Structures

AbstractThe crystal and molecular structures of 1-(m-nitrophenyl)-2,2-dicarboethoxy-3-phenyl-pyrrolidin-5-one (I) and 1-(p-chlorophenyl)-2,2-dicarboethoxy-3-phenyl-pyrrolidin-5-one (II) have been determined by X-ray diffraction methods. (I) crystallizes in the monoclinic space group

Structural and spectroscopic characterization of isotypic sodium, rubidium and cesium acesulfamates

2015 ◽  
Vol 70 (7) ◽  
pp. 491-496 ◽  
Author(s):  
Oscar E. Piro ◽  
Gustavo A. Echeverría ◽  
Eduardo E. Castellano ◽  
Beatriz S. Parajón-Costa ◽  
Enrique J. Baran
Keyword(s):  
Aqueous Solutions ◽  
Single Crystal ◽  
Potassium Salt ◽  
Spectroscopic Characterization ◽  
Molecular Structures ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
X Ray ◽  
Crystal And Molecular Structures

AbstractThree new acesulfamate salts, NaC4H4NO4S, RbC4H4NO4S and CsC4H4NO4S, were prepared by reactions in aqueous solutions and thoroughly characterized. Their crystal and molecular structures were determined by single crystal X-ray diffraction methods. They crystallize in the monoclinic space group P21/a with a = 7.2518(2), b = 8.9414(4), c = 10.5929(4) Å, β = 99.951(3)°, V = 676.52(4) Å3 for the Na salt; a = 7.4663(3), b = 9.6962(4), c = 10.4391(4) Å, β = 95.150(3)°, V = 752.68(5) Å3 for the Rb salt and a = 7.5995(4), b = 9.9439(4), c = 10.8814(6) Å, β = 91.298(5)°, V = 822.08(7) Å3 for the Cs salt, and Z = 4 molecules per unit cell. The three compounds are isotypic to each other and to the previously reported potassium salt. The metal ions are in irregular polyhedral coordination with six neighboring acesulfamate anions through their nitrogen and carbonyl and sulfoxide oxygen atoms. The FTIR spectra of the compounds were also recorded and are briefly discussed.

Two crystal structures of 10,10′-(l,4-phenylene-dimethylidene)-bis-9,10-H-anthracenone

1992 ◽  
Vol 200 (3-4) ◽  
Author(s):  
G. Dewald ◽  
M. Hanack ◽  
E.-M. Peters ◽  
L. Walz
Keyword(s):  
Crystal Structures ◽  
Diffraction Data ◽  
Molecular Structures ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Hydrogen Atoms ◽  
Space Group ◽  
X Ray ◽  
Crystal And Molecular Structures

AbstractThe crystal and molecular structures of dimorphic 10,10′-(1,4-phenylene-dimethylidene)-bis-9,10-H-anthracenone (1) have been determined using X-ray diffraction data. The compound crystallizes either in the monoclinic space groupSince all non-hydrogen atoms are of pure

Crystal and Molecular Structures of the Functional Lithium Cyclopentadienides [Li(tmeda)][R2PCMe2C5H4], R = Ph, Me

2000 ◽  
Vol 55 (11) ◽  
pp. 1005-1010 ◽  
Author(s):  
Ulrich Jürgen Bildmann ◽  
Martin Winkler ◽  
Gerhard Müller Fachbereich
Keyword(s):  
Solid State ◽  
Functional Group ◽  
Molecular Structures ◽  
The Other ◽  
Monoclinic Space Group ◽  
Crystal Data ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Crystal And Molecular Structures

The crystal and molecular structures of the phosphinomethyl-substituted lithium cyclopentadienides [Li(tmeda)][R2PCMe2C5H4], R = Ph (1), Me (2) (tmeda = N,N,N',N'-tetramethylethylenediamine) were determined as their tmeda adducts on the basis of low temperature single crystal X-ray diffraction. (Crystal data: 1: monoclinic, space group P21/n, a = 8.511(5), b = 11.936(2), c = 24.20(1) Å, β = 90.02(3)°, Z = 4.2: monoclinic, space group P21/n, a = 10.887(2), b = 13.326(2), c = 13.131(2) Å, β= 92.872(6)°, Z = 4). In both compounds lithium has a slightly distorted 17 coordination to the cyclopentadienide (Cp) ring. There are no interactions between lithium and the phosphine donors in the solid state as the phosphinomethyl substituents are oriented to the other side of the Cp ring for steric reasons. The isopropene-substituted lithium cyclopentadienide, which is formed as a by-product in the synthesis of phosphinomethyl cyclopentadienides containing a CMe2 bridge, was also structurally characterized as its tmeda adduct [Li(tmeda)][H2C=CMeC5H4] (3). (Crystal data: monoclinic, P21/c, a = 8.00(2), b = 16.701(2), c = 11.942(6) Å, β= 112.68(7)°, Z = 4). As in 1 and 2, lithium is η5 -coordinated to the Cp ring, and there is no interaction of the functional group (isopropene) with lithium.

A comparison of the molecular structures of Dicyclohexyl(N-phenylthiocarbamoyl)-phosphine and Diphenyl(N-phenylthiocarbamoy1)phosphine as determined by X-ray crystallography

1984 ◽  
Vol 37 (10) ◽  
pp. 1991 ◽  
Author(s):  
SW Cowan ◽  
BF Hoskins ◽  
ERT Tiekink
Keyword(s):  
Three Dimensional ◽  
Unit Cell ◽  
Molecular Structures ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Hydrogen Atoms ◽  
Space Group ◽  
X Ray ◽  
X Ray Crystallography ◽  
Conformational Effects

The crystal and molecular structures of the title compounds, (C6H11)2PC(S)N(H)C6H5(1) and (C6H5)2PC(S)N(H)C6H5(2) have been determined by single-crystal three-dimensional X-ray diffraction techniques. Crystals of (1) are monoclinic, space group P21/c, with eight molecules in the unit cell of dimensions a 20.541(4), b 17.784(2), c 10.2564(9) � and β 94.54(1)�; (2) crystallizes in the triclinic space group P1 with two molecules in the unit cell which has the dimensions a 9.242(2), b 9.994(3), c 10.373(3) �, α 68.56(2), β 71.21(2) and γ 86.00(2)�. Both structures were refined by a least-squares procedure, applying anisotropic thermal parameters to all non-hydrogen atoms, with the use of 3119 and 2971 statistically significant reflections for (1) and (2) respectively; final R 0.055 for (1) and R 0.061 (Rw 0.062) for (2). The N, C(l), S moieties of both (1) and (2) display features consistent with the delocalization of π-electrons. There are notable differences in some of the bond angles between (I) and (2) which have been attributed to conformational effects arising from variations in steric pressures; this may account for the observed differences in reactivity between the two compounds.

Metal-thiolate chemistry: The structure of the first adamantane-type cation, [(μ-SPh)6(HgPPh3)4]2+

1993 ◽  
Vol 71 (12) ◽  
pp. 2043-2050 ◽  
Author(s):  
JAGADESE J. Vittal ◽  
Philip A.W. Dean ◽  
Nicholas C. Payne
Keyword(s):  
Molecular Structures ◽  
X Ray Diffraction ◽  
Torsion Angles ◽  
Triclinic Space Group ◽  
X Ray ◽  
Perchlorate Ion ◽  
Cell Dimensions ◽  
Minimum Number ◽  
Counter Data ◽  
The Ideal

The cosmpound [(μ-SC6H5)6{HgP(C6H5)3}4][ClO4]2 crystallizes in the triclinic space group [Formula: see text] as a bis(chloroform) solvate with cell dimensions a = 15.799(4), b = 26.813(5), c = 15.040(5) Å, α = 96.35(2), β = 114.52(2), γ = 100.45(2)° and two formula units per cell. The crystal and molecular structures of this salt were solved by X-ray diffraction techniques using 9898 counter data with I > 2.5σ(I) recorded at −50(2) °C. Refinement of 477 variables by full-matrix least-squares converged at an agreement factor R = 0.046. The cation has adamantane-type stereochemistry with a (μ-SPh)6Hg4 cage and four terminal triphenylphosphine ligands. The S—Cα vectors of the bridging SC6H5 groups adopt the configuration [aae, aae, aee, aee] with the minimum number of two 1,3-axial, axial substituent interactions. There is a significant flattening of the two Hg3S3 rings with two axial substituents into an envelope conformation; each has two torsion angles less than 25°, instead of the ideal values of ±60° in adamantane. One perchlorate ion is doubly solvated by chloroform molecules in an unusual, weakly hydrogen bonded, [ClO4•2HCCl3]− complex.

Complexes containing unsaturated medium rings: The crystal and molecular structures of two rhodium(I) complexes

1978 ◽  
Vol 31 (4) ◽  
pp. 781 ◽  
Author(s):  
R Mason ◽  
GR Scollary
Keyword(s):  
Molecular Structures ◽  
Monoclinic Space Group ◽  
Coordination Geometry ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
X Ray ◽  
Crystal And Molecular Structures ◽  
Square Planar ◽  
Medium Rings

The crystal and molecular structures of two rhodium(I) complexes with long-chain alkyne- or alkene-α,ω-diyldiphosphines have been determined by single-crystal X-ray diffraction techniques. RhCl(CO){But2P(CH2)4C≡C(CH2)4PBut2} crystallizes in the orthorhombic space group Pna21 with a 21.991 (2), b 11.915(1), c 11.890(1) Ǻ and Z 4. The structure was refined by least-squares methods to a conventional R factor of 0.097 for 1768 independent reflections (Mo Kα diffraction data). The rhodium ion is in a square-planar coordination geometry with trans-phosphorus atoms; the unsaturated (alkynyl) group is not bonded to the rhodium. Crystals of RhCl{But2P(CH2)2CH=CH(CH2)2- PBut2} are monoclinic, space group P21/c, a 20.783(12), b 8.580(4), c 14.799(9) Ǻ, β 100.70(2)°, Z 4. The structure analysis has converged to R 0.069 for 1417 reflections (Mo Kα diffractometry); the coordination geometry of the rhodium is again planar with the ethylenic group occupying a single bonding site. The effect of ring size on the rhodium-phosphorus bond lengths is discussed.

Comparison of σ-acyl and σ-perfluoroacyl groups as ligands: Crystal and molecular structures of the platinum(II) complexes trans-PtCl(COR)(PMePh2)2 (R = Me,CF3)

1982 ◽  
Vol 35 (7) ◽  
pp. 1311 ◽  
Author(s):  
MA Bennett ◽  
K Ho ◽  
JC Jeffery ◽  
GM Mclaughlin ◽  
GB Robertson
Keyword(s):  
Three Dimensional ◽  
Molecular Structures ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Crystal And Molecular Structures ◽  
Unique Data ◽  
Trans Influence ◽  
Small Deformations

Crystal and molecular structures of the title compounds have been determined from three dimensional X-ray diffraction data recorded on a four-circle diffractometer. Crystals of the acetyl complex, trans-PtCl(COMe)(PMePh2)2,(1), are monoclinic, space group P2,1/c, with a 12.9709(5), b 11.1024(5), c 277535(9) Ǻ, β 94.75(1)° and Z 6. Crystals of the trifluoroacetyl complex, trans-PtCl(COCF3)- (PMePh2)2, (2), are monoclinic, space group P21/n (non-standard setting of P21c), with a 11.4246(7), b 15.5750(7), c 15.4200(8) Ǻ, β 90.54(1)° and Z 4. For (I), with Z 6, the unit cell contains one set of four equivalent molecules in the general equipoint and one set of two equivalent (disordered) molecules located at inversion centres. The four molecules in (2) comprise a single equivalent set in the general equipoint. Least-squares analyses converge with R 0.042 for (1) (5696 unique data) and R 0.025 for (2) (3933 unique data). Molecules of both complexes exhibit small deformations from planar towards tetrahedral platinum geometry; the acyl and coordination planes are approximately orthogonal. The phosphine substituents in (2) and in the 'general' molecules in (1) are approximately eclipsed, and approximately eclipse the Pt-C (acetyl) bonds. In the 'special' molecules in (1) the phosphines are constrained to adopt the mutually staggered conformation found in the alkyl analogues trans-PtClR(PMePhM2)2 (R = Me, CF3, C2F2). Important comparative lengths in (1) (general molecule) and in (2) (in square brackets) are: Pt-C 2.028(6) [1.960(4)] A, Pt-Cl 2.430(2) [2.390(1)] Ǻ, Pt-P 2.301(2), 2.297(2) [2.316(1), 2.321(1)] A, C-O 1.182(8) [1.210(5)] 8, and C C (acetyl) 1.488(10) [1.547(6)] A. The trifluoroacetyl ligand forms a shorter and presumably stronger bond with platinum, and exerts a larger cis- and a smaller trans-influence than the acyl ligand. The smaller trans-influence of the trifluoroacetyl ligand is consistent with the expectation from platinum-chlorine stretching frequencies (v(Pt-Cl)).

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