Molecular Structure Of Bis Research Articles

Crystal and molecular structure of bis(dimethylphenylphosphine)(3,4-diacetyl-4-hexene-2-one-5-olato-C 3,O)platinum(II)

The crystal and molecular structure of the first cyclometallated platinum(II) complex of 1,1,2,2-tetraacetylethane {bis(2,4-pentanediones)-3,4-diacetyl-2,4-hexadiene-2,5-diol (H 2-dahd)}, [Pt(dahd-C 3,O)(PMe 2Ph) 2], was determined by X-ray analysis.

Deprotonated thioamides as thiolate S-donor ligands with a high tendency to avoid M-S-M bridge formation: crystal and molecular structure of bis(2-hydroxy-5-methylacetophenone N,N-dimethylthiosemicarbazonato)dinickel

The crystal structure of [Ni(tmtssA)] 2 (1a) (tmtssA= 2-hydroxy-5-methylacetophenone N,N-dimethylthiosemicarbazonato) is surprising in having a phenolate O-bridge rather than the expected imino thiolate S-bridge. This implies that deprotonated thioamides such as tmtssA, which bind in the imino thiolate form, have a much lower bridging tendency than alkane- or arenethiolates

Isolation, reactivity, and molecular structure of bis(2,2'-bipyridine)(.mu.-N-acetyl-L-cysteinato-S)diplatinum: model of the interaction of platinum with protein sulfur residues

Isolation, reactivity, and molecular structure of bis(2,2'-bipyridine)(.mu.-N-acetyl-L-cysteinato-S)diplatinum: model of the interaction of platinum with protein sulfur residues

Synthesis and molecular structure of bis(tetraphenylcyclopentadienyl)tetrakis(μ-trifluoroacetato)divanadium(III)

The reaction between V(η-C 5HPh 4) 2 and trifluoracetic acid in benzene at 115-120 °C produces (η-C 5HPh 4V(μ- O 2CCF 3) 4V(η-C 5HPh 4) ( I). Recrystallization from THF yields I·2THF, which crystallizes in the space group P 1 with a=12.048(8), b=15.607(5), c=9.689(6) Å, α=97.16(4), β=108.62(5), γ=68.01(3)°, V=1601(2) Å 3, and Z=1 at −110 °C. Refinement of 442 variables on 3772 reflections 1> 3σ( 1) converged to R=0.060 and R w=0.075. The structure contains four bridging carboxylates, terminal η-C 5HPh 4 ligands staggered with respect to one another, and a non-bonding VV separation of 3.752(1) Å. The structural data suggest the steric effect of the η-C 5HPh 4 ligand rivals that of η-C 5Me 5.

EPR studies on bis(diisopropyldithiophosphato)copper(II) magnetically diluted in the corresponding palladium(II) and platinum(II) single crystals and crystal and molecular structure of bis(diisopropyldithiophosphato)palladium(II) host lattice

The EPR spectra of single-crystal samples of 63Cu[(Pr i 2O) 2PS 2] 2 magnetically diluted in the corresponding palladium(II) and platinum(II) host lattices were studied at room temperature and eigen-values of the A and g tensors evaluated. The results obtained show that both the samples have approximately axial symmetry (Δ A = A x - A y ⪕ 3 G; Δ g = g x - g y ⪕ 0.03) with one molecule per unit cell in both host lattices. It is found that g z coincides with A z whereas the angle between g x and A x ( g y and A y ) is 27° and 11° for 63Cu/Pt[(Pr i 2O) 2PS 2] 2 and 63Cu/Pd[(Pr i 2O) 2PS 2] 2, respectively. The data about a quadrupole interaction obtained was considered with special attention, because their values are close to the experimental error. In view of this, the possibility for determining Q values from simulated powdered EPR spectra was explored. The results show, however, inapplicability of this approach too. The crystal and molecular structure of bis(diisopropyldithiophosphato)palladium(II) was determined.

ChemInform Abstract: First Representative of Thiosalicylidene Oximates. Synthesis and Molecular Structure of Bis(thiosalicylidene‐O‐methyl‐oximato)nickel(II) .

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N-(Substituted phenylhydroxynaphthylaldiminate) nickel(II) complexes : A structural and vibrational study

The crystal and molecular structure of bis-( N-phenyl-1-hydroxy-2-naphthylaldiminate) nickel(II) ( 1) have been determined by x-ray crystallography. The compound crystallizes in the triclinic space group P1, No. 2 with one molecule in the unit cell. The metal adopts a trans-planar tetracoordination geometry with N and O as electron donor atoms. The molecule is stepped with the planes of two naphthyl groups parallel, each one making a dihedral angle of 20.4° with the coordination plane. The infrared spectrum and a normal coordinate treatment, based on a simplified molecular model, are discussed and related to the crystal structure. The bands near 390 and 290 cm −1 have been assigned to the Ni O and Ni N stretching vibrations, respectively. The corresponding force constants were estimated to be 1.28 and 0.78 mdyn Å −1. The influence of variation of the nature of the Schiff base ligand on structure 1 has been studied by including in the vibrational analysis the bis- N-(Y-phenyl)-2-hydroxy-1-naphthylaldiminate nickel(II) complexes, where substituents Y are o-OCH 3 ( 2), m-OCH 3 ( 3) and m-NO 2 ( 4). The results indicated a slightly lower electronic density distribution on the chelate ring in complex 1, particularly on the Ni O bond, suggesting a stability order 1 ≈ 2− 4. This difference arises mainly from the position of the hydroxynaphthylaldiminate group.

Ligand addition reactions and the electron-transfer properties of tin dichloride dihydrate and tin tetrachloride pentahydrate. Molecular structure of bis(ethyl cysteinato)tin(II)

The synthesis and characterization of the tin(II) compounds Sn(ECD) and Sn(CEE) 2 and the tin(IV) complex Sn(ECD) 2 , where H 2 ECD is N,N'-1,2-ethylenediylbis(L-cysteine) diethyl ester and HCEE is L-cysteine ethyl ester, are reported. H 2 ECD can be described in a general sense as a ligand with a N 2 S 2 coordination site while the related complex HCEE has a NS coordination site following deprotonation of each thiol group on H 2 ECD or HCEE

First preparation of a sulfurane with four carbon–sulfur bonds: synthesis and molecular structure of bis(2,2′-biphenylylene)sulfurane

The first stable pentacoordinated sulfur compound with four carbon–sulfur bonds, bis(2,2′-biphenylylene)sulfurane 1, is prepared and its molecular structure is determined by X-ray crystallographic analysis.

Preparation and Reactivity of Planar Trigonal Copper(I) Compounds. Crystal Structure of Bis(2-Thioxohexamethyleneimine)Copper(I) Bromide

Abstract The crystal and molecular structure of bis(2-thioxohexamethyleneimine)copper(I) bromide, Cu(tclH)2Br, is reported. The compound is a three-coordinate monomer and crystallizes in space group P21/n with a = 8.807(l), b= 15.893(1), c= 12.385(1) Å, β = 105.98(1)[ddot] and Z=4. It is symmetrically folded with respect to the Cu-Br bond, the copper atom being slightly elevated (0.036 A) relative to the plane defined by the two sulfur and one bromine donor atoms. The two equivalent Cu-S bonds are 2.228(2) Å and the Cu-Br bond distance is 2.385(1) Å, the interbond angles around copper being close to 120[ddot]. Its reactivity towards small molecules (e.g., CS2, CO2) and Lewis bases (e.g., pyridine, PPh3, AsPh3), has also been investigated.

A study of the copper(II) chloride-trimethylamine system. Crystal and molecular structure of bis[trimethyl(chloromethyl)ammonium]tetrachlorocuprate(II), [Me 3NCH 2Cl] 2[CuCl 4

Treatment of anhydrous CuCl 2 with excess NMe 3 at room temperature gives the yellow mono-adduct CuCl 2·1.1NMe 3 ( I). Attempted recrystallization of I from CH 2Cl 2 provides the orange tetrachlorocuprate(II) salt [Me 3NCH 2Cl] 2[CuCl 4] ( II). The same product is obtained from direct treatment of CuCl 2 with a mixture of NMe 3/CH 2Cl 2. The structure of II has been determined by conventional X-ray diffraction techniques: crystals are monoclinic, space group P2 1/n with cell constants a=17.20(1), b=11.78(1), c=9.067(7) Å, β=90.5(1)°, U=1837.0 Å 3, Z=4. The final R value for 1620 unique reflections ( I> 2σ( I)) is 0.062 ( R w=0.064). The structure consists of two independent [Me 3NCH 2Cl] + cations and one discrete [CuCl 4] 2− anion whose geometry is intermediate between tetrahedral and square planar with trans ClCuCl angles of 132.5(1) and 134.4(1)° and CuCl distances in the range 2.232(3)–2.253(3) Å.

Synthesis and study of mixed ligand monomer Cu(I) compounds with CuAs bonds. Crystal and molecular structure of bis(triphenylarsine)-(2-thioxohexamethyleneimine)copper(I) bromide

A new series of mixed ligand coordination compounds with CuAs bonds is synthesized by the reaction of Cu(AsPh 3) 3X, where XCl, Br, or [Cu(AsPh 3)I] 4 with 2-thioxohexamethyleneimine (ω-thiocaprolactam, tclH) in acetone or by the addition of triphenylarsine to Cu(tclH) 2X in methanol/chloroform. The products of both reactions are formulated as Cu(tclH)(AsPh 3) 2X, on the basis of their elemental analyses, IR, 1H NMR and UV-Vis spectral data. The crystal structure of the bromo compound is reported and discussed with respect to that of Cu(tclH) 2(AsPh 3)Br. The compound crystallizes in the monoclinic space group C2/ c, with a=41.981(8), b=9.961(2), c=19.087(2) Å, β=101.09(1)°, 8 discrete molecules being present in the unit cell. The copper environment is a distorted tetrahedron, with two inequal CuAs bonds, which are 2.411(2) and 2.372(2) Å, respectively. The CuBr and CuS bond lengths are equal to 2.456(3) and 2.313(4) Å, respectively, while the bond angles around copper vary from 104.4(0)° for As1CuS to 116.1(1)° for As1CuAs2.

Molecular geometry of bis ( N-chloromethyl)nitramine from gas electron diffraction

The molecular structure of bis ( N-chloromethyl) nitramine has been determined by gas electron diffraction. The bond lengths ( r g), bond angles and angles of torsion (φ) with estimated total errors in parentheses are as follows: NO 1.216(3) Å NN 1.422(5) Å CN 1.443(4) Å ClC 1.803(4) Å CH 1.109(9) Å ONO 128.0(14)° CNN 116.3(4)° CNC 124.8(9)° ClCN 111.6(5)° HCN 110.3(9)° φ CN 78.9(7)° φ NN 2.6(15)° The amine nitrogen has an essentially planar bond geometry. This molecule has practically C 2 symmetry. The two ClC bonds point to opposite sides of the planar C 2NNO 2 skeleton.

Bonding properties of Cu(II)-O chromophores: electronic and molecular structure of bis(imidazole)bis( N-methylacetamide)bis(perchlorato)copper(II)

The crystal and molecular structure of bis(imidazole)bis( N-methylacetamide)bis(perchlorato)copper(II) has been determined using three-dimensional X-ray diffraction data. The complex crystallizes in monoclinic P2 1/ c with Z = 2, a = 7.720(2), b = 16.169(3), c = 8.742(2) Å and β=96.08(1)°. Least-squares refinement of the structure yielded a final R value of 6.62% and a R w of 7.55% for 1388 independent reflections at 294 K. The copper(II) ion is coordinated by six ligands to form a centrosymmetrically elongated octahedron with CuN(imidazole) 1.969(6), CuO( N-methylacetamide) 1.982(5) and CuO(ClO 4 −) 2.760(10) Å. The molecules are held together with hydrogen bonding between imidazole and perchlorate and between N-methylacetamide and perchlorate. The imidazole ligands, having donating nitrogens with mainly ‘pyrrole’ character as evident by the nearly equal bond lengths of the CN(H) and CN(Cu) bonds of the rings, form strong σ-bonds with the central copper ions. The N-methylacetamide ligand, having a very short CO (1.159(12) Å) and a long NC(O)(1.330(13) Å) bond, suggests a canonical structure with restricted π-delocalization. The deconvoluted Gaussian component dd bands of the title complex and the pyridine N-oxide analogues are analyzed and assigned with reference to their molecular structures. The bonding properties of Cu(II)O are deduced: in elongated octahedral copper(II) complexes, pyridine N-oxide is a moderately strong σ-donor and a strong π-donor, whereas N-methylacetamide is merely a moderately strong σ-donor.

Correlations between nuclear magnetic resonance spectra and crystal structure. III. A13C nuclear magnetic resonance study in the solid state of bis(xanthato) complexes of mercury(II); The crystal and molecular structure of bis(n-propyl-dithiocarbonato)mercury(II)

The cross-polarization magic angle carbon-13 nmr spectra of a series of bis(xanthato) complexes of mercury(II) are reported; [Hg(S2COR)2] n R=Me, Et, n Pr and i Pr. The spectra correlate well with the known crystal structures of theR=Me, Et, and i Pr compounds and with that of theR= n Pr derivative for which a single-crystal X-ray diffraction study is also reported. The X-ray analysis of [Hg(S2CO n Pr)2] n shows that this compound adopts a two-dimensional structure comprised of connected 16-membered rings which arise as a result of bridgingn-propylxanthate ligands. The mercury atom lies on a crystallographic twofold axis of symmetry and exists in a distorted tetrahedral geometry with two unique Hg-S bond distances of 2.418(3) and 2.835(4) A. Unit-cell dimensions for [Hg(S2CO n Pr)2] n are:a=7.371(3),b=8.534(4),c=11.618(4) A andZ=2 for the orthorhombic space groupP21212. The structure was refined by a full-matrix least-squares procedure to finalR=0.047 andR w =0.044 for 899 reflections withI≥2.5σ(I). While the solid state nmr spectra provide information on molecular (and crystallographic) symmetry they do not provide sufficient detail to enable structure determination for the [Hg(S2COR)2] compounds.

Redetermination of the Crystal and Molecular Structure of Bis(pentafluorophenyl)mercury

The crystal and molecular structure of Bis(pentafluorophenyl)mercury, Hg(C6F5)2, was redetermined from diffractometer data yielding greatly improved structural parameters. The geometry at mercury is virtually linear (C—Hg—C 178.8(3)°), with mercury carbon bond lengths of 2.047(6) and 2.052(6) Å.

A pyrazole ligand yielding both chloro-bridged dinuclear and tetranuclear copper(II) compounds. The crystal and molecular structure of bis[μ-chloro-chloro(3,4-dimethyl-5-phenylpyrazole) (4,5-dimethyl-3-phenylpyrazole)copper(II)] and of (μ 4-oxo)hexakis(μ-chloro)tetrakis(3,4-dimethyl-5-phenylpyrazole)tetracopper(II)

The reaction of CuCl 2·2H 2O and 3(5),4-dimethyl-5(3)-phenylpyrazole (hereafter Hdmppz) gives green crystals that analyze as CuCl 2(C 11H 12N 2) 2 ( 1). The green filtrate produces brown crystals of composition Cu 4OCl 6(C 11H 12N 2) 4 ( 2). The crystal structure of both compounds was determined from single-crystal X-ray data. Crystals of bis[μ-chloro-chloro-(3,4-dimethyl-5-phenylpyrazole)-(4,5-dimethyl-3-phenylpyrazole)copper( II)] ( 1) are triclinic, space group P 1 ; a = 9.071(1), b = 11.008(1), c = 11.358(1) Å, α = 93.42(1), β = 97.50(1), γ = 96.16(1)°, Z = 1. The dinuclear unit is located on a crystallographic inversion center. The copper ion is five-coordinated by two pyrazole nitrogen atoms and one bridging and one non-bridging chloride anion. The coordination is best described as a distorted square pyramid with the long bridging chloride as the top. Surprisingly the two pyrazole ligands are coordinating through different nitrogen atoms, one through the nitrogen atom close to the phenyl substituent and the other through the nitrogen close to the methyl substituent. Crystals of (μ 4-oxo)hexakis(μ-chloro)tetrakis(4,5-dimethyl-3-phenyl-pyrazole)tetra-copper(II) ( 2) are monoclinic, space group I2/ a; a = 20.836(1), b = 11.161(1), c = 22.996(1) Å, β = 104.54(1)°, Z = 4. The copper ions are coordinated by five ligands in a trigonal-bipyramidal arrangement. The pyrazole nitrogen and the oxo-anion form the two tops of the bipyramid and the chlorides form the basal plane. Magnetic susceptibility measurements of 1 and 2 show that there is considerable antiferromagnetic interaction in these compounds as can be expected. For 1 the experimental data could be fitted to a model for a dinuclear compound with 2 J as the singlet triplet splitting and zJ′ the inter-dinuclear exchange. The best fit was found for g = 2.13, J/k = −5.8 K and zJ′/k = -0.22 K. For 2 a model was used with two different exchange parameters J a and J b. The best fit was obtained for g = 2.11 and J a/k = −51 K and J b/k= −33 K.

Structural and Luminescence Study of the 3:2 Complex between Europium Nitrate and the B Isomer of Dicyclohexyl-18-crown-6

The crystal and molecular structure of bis[dinitrato-(2,4,8,15,18,21-hexaoxatricyclo[20.4.0.09,14]hexacosane)europium(III)]pentakis(nitrato)europiate(III) [Eu(NO3)2LB]2([Eu(NO3)5]), has been determined at 170 K from single-crystal X-ray diffraction. The complex crystallizes in the monoclinic space group P21/n (ITC No. 14): a = 16.338(3) A, b = 15.704(3) A, c = 24.474(4) A, β = 97.73(1)°, Z = 4. The structure was refined to a final R value of 0.058 (Rw = 0.060). The asymmetric unit contains three independent ions lying on general positions: [Eu(NO3)5]2− and two distinct [Eu(NO3)2LB]+ cations with the macrocyclic ligand in the cis-anti-cis conformation (B-isomer). The EuIIIions are 10-coordinate with the following mean bond lengths: Eu–O(nitrate) = 2.48(2) A in the anion and 2.45(2) A in the two cations, Eu–O(ether) = 2.56(8) and 2.55(5) A. Small but significant differences are observed between the two complex cations, especially with respect to the positions of the cyclohexyl substituent. A conformational analysis performed on the six O-atoms of the complex cations confirms the predictions of a simple model. The metal ion sites of the complex have been probed by high-resolution excitation and emission spectra at 296 and 77 K. The 5D07F0 excitation spectrum displays two main bands along with several other minor components. A detailed analysis of the corresponding and selectively excited emission spectra leads to the observation of three types of spectra corresponding to the three crystallographically different EuIII ions. Moreover, three minor sites are identified, one anionic and two cationic, with a population equal to ca. 10% of the population of the main sites. We interpret this finding as reflecting the presence of molecules with slightly different conformations.

Crystal and Molecular Structure of Bis(pyridine)N,N′‐o‐phenylen‐bis[2‐cyan‐2‐ethoxycarbonyl‐vinyl‐amido(–)]‐iron(II)‐Pyridine

AbstractThe crystal and molecular structure of bis(pyridine)N,N′‐o‐phenylen‐bis[2‐cyan‐2‐ethoxycarbonyl‐vinyl‐amido(–)]iron(II)‐pyridine were determined by X‐ray structure analysis. It crystallizes in the monoclinic space group P 21/c with cell parameters a = 9.866(23), b = 19.491(46), c = 16.992(22) Å, and β = 95.19(1)°. The structure was solved by the heavy atom method and refined to R = 0.125. The coordination geometry around the iron atom is octahedrally distorted with the two pyridine molecules in the axial positions.

The oxygenation of flavonol by copper(I) and copper(II) flavonolate complexes. The crystal and molecular structure of bis(flavonolato)copper(II)

Flavonol is oxygenated to the corresponding depside catalysed by Cu1 and CuII flavonolate complexes; X-ray structure determination of bis(flavonolato)copper(II)·2CHCl3 shows that the two flavonolate ligands are coordinated to CuII through their 3-hydroxy and 4-carbonyl groups to result in a square planar geometry around copper(II).