Molecular Structure Of Bis Research Articles

One-pot thermo-induced radical-radical oxidative cross-coupling for symmetrical dimeric thiadiazole monosulfide formation

The production of heterocyclic sulfide is the key building block in various applications, especially in the field of medicinal chemistry. Currently, heterocyclic sulfide was synthesized via deoxygenation of sulfoxide or cross coupling between sulfur sources and halogen compounds. However, these conventional methods suffer from drawbacks such as the use of toxic solvents, harsh reaction conditions, the requirement for transition metal catalysts, inert conditions, and the generation of toxic and corrosive halide-containing waste. In this study, a milder approach using hydrogen peroxide-mediated oxidative cross-coupling of 5-alkylsulfanyl-[1,3,4]thiadiazole-2-thiol successfully produces symmetrical dimeric thiadiazole monosulfide with an isolated yield of 73‒87 %. The molecular structure of bis(2-octylsulfanyl-[1,3,4]thiadiazolyl)-5,5′-sulfide was confirmed by X-ray crystal structure analysis. Interestingly, the formation of dimeric thiadiazole monosulfide undergoes a one-pot thermo-induced pathway. Density functional theory (DFT) indicates the formation of thiadiazole monosulfide is thermodynamically favorable through the cross-coupling reaction between thiadiazole thiyl radical and thiadiazole carbon-centered radical.

Synthesis and Crystal Structures of Bis(diallydithiocarbamato)zinc(II) and Silver(I) Complexes: Precursors for Zinc Sulfide and Silver Sulfide Nanophotocatalysts.

We report the preparation and crystal structures of bis(diallydithiocarbamato)zinc(II) and silver(I) complexes. The compounds were used as single-source precursors to prepare zinc sulfide and silver sulfide nanophotocatalysts. The molecular structure of bis(diallydithiocarbamato)zinc(II) consists of a dimeric complex in which each zinc(II) ion asymmetrically coordinates with two diallydithiocarbamato anions in a bidentate chelating mode, and the centrosymmetrically related molecule is bridged through the S-atom that is chelated to the adjacent zinc(II) ion to form a distorted trigonal bipyramidal geometry around the zinc(II) ions. The molecular structure of bis(diallydithiocarbamato)silver(I) formed a cluster complex consisting of a trimetric Ag3S3 molecule in which the diallydithiocarbamato ligand is coordinated to all the Ag(I) ions. The complexes were thermolyzed in dodecylamine, hexadecylamine, and octadecylamine (ODA) to prepare zinc sulfide and silver sulfide nanoparticles. The powder X-ray diffraction patterns of the zinc sulfide nanoparticles correspond to the hexagonal wurtzite while silver sulfide is in the acanthite crystalline phase. The high-resolution transmission electron microscopy images show that quantum dot zinc sulfide nanoparticles are obtained with particle sizes ranging between 1.98 and 5.49 nm, whereas slightly bigger silver sulfide nanoparticles are obtained with particle sizes of 2.70-13.69 nm. The surface morphologies of the ZnS and AgS nanoparticles capped with the same capping agent are very similar. Optical studies revealed that the absorption band edges of the as-prepared zinc sulfide and silver sulfide nanoparticles were blue-shifted with respect to their bulk materials with some surface defects. The zinc sulfide and silver sulfide nanoparticles were used as nanophotocatalysts for the degradation of bromothymol blue (BTB) and bromophenol blue (BPB). ODA-capped zinc sulfide is the most efficient photocatalyst and degraded 87% of BTB and 91% of BPB.

Crystal structure and vibrational spectra of bis(2-isobutyrylamidophenyl)amine: a redox noninnocent ligand.

The molecular structure of bis(2-isobutyrylamidophenyl)amine (H3LNNN) has been determined from single-crystal X-ray diffraction data. The crystal packing of H3LNNN is governed by the N-H···O and C-H···O hydrogen-bonding and C-H···π stacking interactions between the vicinal molecules. The intermolecular interactions in the crystal structure of H3LNNN have been also examined via Hirshfeld surface analysis and fingerprint plots. The Hirshfeld surface analysis showed that the important role of N-H···O and C-H···π interactions in the solid-state structure of H3LNNN. The molecular structure, vibrational frequencies, and infrared intensities of H3LNNN were computed by ab initio HF and DFT (B3LYP, B3PW91, and BLYP) methods using the 6-31G(d,p) basis set. The computed theoretical geometric parameters were compared with the corresponding single crystal structure of H3LNNN. The harmonic vibrations calculated for the title compound by the B3LYP method are in good agreement with the experimental IR spectral data. The theoretical vibrational spectrum of the H3LNNN compound was interpreted through potential energy distributions using the SQM Version 2.0 program. The performance of the used methods and the scaling factor values were calculated with PAVF Version 1.0 program.

Bis(pyrazol-1-yl)methane-4,4′-dicarboxylic Acid

The molecular structure of bis(pyrazol-1-yl)methane-4,4′-dicarboxylic acid (H2bpmdc) was determined by single crystal X-Ray diffraction analysis. The compound crystallizes in a monoclinic crystal system; the unit cell contains four formula units. The molecules of H2bpmdc are linked into zig-zag chains by intermolecular carboxyl–carboxyl hydrogen bonds. Other types of supramolecular interactions, namely, CH···N and CH···O short contacts, CH–π interactions and carbonyl–carbonyl interactions were detected in the crystal structure.

Crystal and molecular structure of bis(N-(diethylcarbamothioyl)cyclohexane carboxamido)copper(II) complex

Herein, we describe the synthesis and characterization of bis(N-(diethylcarbamothioyl)cyclohexane carboxamido)copper(II) complex, cis-[Cu(L-κ2S,O)2], has been prepared by the reaction of N-(diethyl carbamothioyl)cyclohexanecarboxamide ligand with copper(II) acetate. The green colored crystals of the complex were obtained by slow evaporation of their dichloromethane:ethanol solution (2:1, v:v). The crystal structure of cis-[Cu(L-κ2S,O)2] was obtained by single-crystal X-ray diffraction. The crystal structure reveals an monoclinic C2 (no. 5) space group with cell parameters a = 14.848(3) Å, b = 10.543(2) Å, c = 10.511(2) Å, β = 123.84(3)°, V = 1366.7(7) Å3, Z = 2, T = 153(2) K, μ(MoKα) = 0.979 mm-1, Dcalc = 1.327 g/cm3, 4979 reflections measured (6.6° ≤ 2Θ ≤ 50.68°), 2243 unique (Rint = 0.0223, Rsigma = 0.0444) which were used in all calculations. The final R1 was 0.0225 (>2sigma(I)) and wR2 was 0.0490 (all data). The angular structural index parameter, τ4, is equal to 0.40, which confirms the distorted square planar geometry for the title compound. The puckering parameters (q2 = 0.015(3) Å, q3 = 0.576(3) Å, QT = 0.577(3) Å, θ = 1.6(3)° and φ = 20(11)°) of the title complex show that the cyclohexane ring adopts a chair conformation. The two ethyl groups of the diethyl amine group have anti-orientation with respect to one another. The crystal packing shows the molecules stacked in parallel sheets along [010], accompanied by C3-H3A···O1ⁱ (i -x, +y, 1-z) intermolecular contact.

Silicon phthalocyanine: Vapor pressure and photovoltaic properties

The basic physicochemical properties and molecular structure of bis-(thrimethylsiloxy).phthalocyaninato silicon [SiPc(OSiMe3)2] are investigated. The temperature of melting of this complex was measured by the DSC method in the temperature interval 20–520 °C (Tm=497 °C). Thermogravimetric analysis data showed mass loss occurs in the temperature range 275−500 °C. The mass loss in this temperature range is 96 %. Mass spectrometric studies of the composition of the gaseous phase of [SiPc(OSiMe3)2] was performed in the temperature range up to 450 °C. It was found that the complex is sublimated in monomeric form. The vapor pressure of the compound was determined as a function of temperature by the Knudsen effusion method. Based on the data obtained, the thermodynamic parameters of the sublimation process are calculated. The X-ray diffraction study revealed that molecular geometric parameters of [SiPc(OSiMe3)2] are varied slightly upon changing of temperature. The photovoltaic properties of [SiPc(OSiMe3)2] studied with heterojunction solar cell of configuration of ITO/complex /C60/Bphen/Al. The operating characteristics of the cell turned out comparable with the characteristics of earlier designed analogues devices based on phthalocyanine complexes of Cu, Zn and Sn.

Synthesis, characterization, luminescent properties and biological activities of zinc complexes with bidentate azomethine Schiff-base ligands

A series of zinc complexes with a bidentate azomethine Schiff base ligands derived from 2-tosylaminobenzaldehyde, 2-hydroxy-, 2-hydroxy-5-methoxybenzaldehydes, 2-hydroxynaphthaldehyde and 3,4-dimethoxyphenylethylamine were synthesized by chemical and electrochemical methods. All compounds were characterized on the basis of C, H, N elemental analysis, FT-IR, 1H NMR, UV-vis and photoluminescence studies. The local atomic structures of complexes were determined from analysis of EXAFS and XANES of Zn K-edges. The molecular structure of bis{2-[(E)-2-(3,4-dimethoxyphenyl)ethyliminomethyl]-4-methoxyphenol}zinc(II) was determined by X-ray single-crystal diffraction. The fluorescence spectra show that these complexes in DMSO solutions at room temperature emit bright blue and green luminescence at 428–497 nm. The assignment and the nature of the bands in experimental UV–Vis spectra of complexes were analyzed using time-dependent (TD) DFT calculations. The azomethines and complexes of zinc have been screened for their antibacterial, protistocidal, and fungistatic activities against Penicillium italicum, Colpoda steinii, Escherichia coli 078 and Staphylococcus aureus P-209, and the results are compared with the activity of sulfadimethoxine, toltrazuril and fundazol.

Reactions of diiron(III) tris[(1-hydroxyethylidene)diphosphonate] tetrahydrate and iron(III) tris[(1-hydroxyethylidene)diphosphonate] tetrahydrate with p-aminobenzoic acid. Molecular structure of bis(4-carboxyphenylaminium) (1-hydroxyethylidene)diphosphonate

Diiron(III) tris[(1-hydroxyethylidene)diphosphonate] tetrahydrate and iron(III) tris[(1-hydroxyethylidene) diphosphonate] tetrahydrate react with p-aminobenzoic acid in water to form diiron(III) pentakis(4-carboxyphenylaminium) tris(1-hydroxyethylidene)diphosphonate dihydrate and iron(III) hexakis(4-carboxyphenylaminium) tris(1-hydroxyethylidene)diphosphonate dihydrate. The crystal structure of bis(4-carboxyphenylaminium) (1-hydroxyethylidene)diphosphonate obtained by the reaction of (1-hydroxyethylidene)diphosphonic acid with p-aminobenzoic acid in methanol was established.

Bis(κ2S,Sʹ-di(isopropyl)dithiocarbamato)nickel(II): Anagostic C–H⋅⋅⋅Ni interactions and physical properties

The molecular structure of bis(κ2S,Sʹ-di(isopropyl)dithiocarbamato)nickel(II) has been examined by single crystal X-ray diffraction. The data reveal a C–H⋅⋅⋅Ni anagostic interaction arising from the interaction of two non-equivalent molecules within the crystal. Thermal analysis data show that the complex decomposes at ∼330 °C. The structure of the resultant NiS material was examined using scanning electron microscopy and energy dispersive X-ray spectroscopy which revealed NiS nanowires.

Theoretical and experimental investigations on molecular structure of bis(2-methoxy-4-allylphenyl)oxalate

The aim of this study is to find out the molecular characteristic and structural parameters that govern the chemical behavior of a new bis(2-methoxy-4-allylphenyl)oxalate compound and to compare predictions made from theory with experimental observations. The title compound, bis(2-methoxy-4-allylphenyl)oxalate (I), (C22H22O6), has been synthesized. The compound has been characterized by elemental analysis, IR, 1H NMR, 13C NMR spectroscopies and single crystal X-ray diffraction techniques. Optimized molecular structure, harmonic vibrational frequencies have been calculated by B3LYP/6-311G(d,p) method using density functional theory (DFT). 1H and 13C nuclear magnetic resonance (NMR) chemical shifts of the molecule have been investigated by the Gauge-Invariant Atomic Orbital (GIAO) method. The calculated results show that the predicted geometry can well reproduce structural parameters. To estimate chemical reactive sites of the molecule, molecular electrostatic potential map (MEP), frontier molecular orbitals (FMOs), Mulliken population method and natural population analysis (NPA) have been calculated for the optimized geometry of the molecule. To investigate the NLO properties of the molecule, the electric dipole, the polarizability and the first hyperpolarizability have been calculated. In addition, thermodynamic properties have also been studied.

Synthesis and Physico-Chemical Studies of a New Noncentrosymmetric Bis[N-(2-hydroxyethyl)piperazine-1,4-diium] Tetrakis(hydrogen oxalate) Trihydrate: [C6H16N2O]2(HC2O4)4·3H2O

The new noncentrosymmetric oxalate with the general formula [C6H16N2O]2(HC2O4)4·3H2O, has been synthesized and single crystals were grown from aqueous solution by slow evaporation technique. Single crystal X-ray diffraction study on grown crystal reveals that they belong to triclinic system with space group P1. The unit cell dimensions are: a = 5.688(2) A, b = 8.315(2) A, c = 16.634(3) A, α = 96.63(2)°, β = 99.81(3)°, γ = 110.01(2)° with V = 715.4(3) A3 and Z = 1. The structure has been solved using a direct method and refined to a reliability R factor of 0.052. The structure is built up from anionic chains parallel to the a-axis. These chains are interconnected by the organic cations and water molecules via hydrogen bonds so as to build a three dimensional arrangement. FT-IR spectrum confirms the presence of the functional groups in the synthesized material. The 13C CP-MAS NMR spectrum is in agreement with the X-ray structure. UV–Vis spectrum indicates that the crystal is transparent in UV and visible region with a lower cutoff wavelength of 212 nm. The DSC curve indicates that the crystal is thermally stable up to 330 K. The molecular structure of bis(N-(2-hydroxyethyl)piperazine-1,4-diium) Tetrakis(hydrogen oxalate) Trihydrate is formed by N-(2-hydroxyethyl)piperazine-1,4-diium cations, oxalate anions and water molecules held together by means of N–H⋯O, C–H⋯O, O–H⋯OW and OW–H⋯OW(O) hydrogen bonds to form three-dimensional network.

4-tBu-2,6-{P(O)(OiPr)2}2C6H2Sn(PPh3)Cr(CO)5]ClO4 – a salt containing a cationic triphenylphosphane-stabilized organostannylene transition metal complex

AbstractThe isolation and molecular structure of bis(di-

Interaction of pentaphenylantimony with acetylenedicarboxylic acid. Molecular structure of bis(tetraphenylantimony) acetylenedicarboxilate

Interaction of pentaphenylantimony with acetylenedicarboxylic acid. Molecular structure of bis(tetraphenylantimony) acetylenedicarboxilate

Catenar bimetallomesogens derived from quinoxaline–salicylaldimine conjugates

The preparation, characterization, and mesomorphic properties of two series of tridentate N-salicylidene-2-hydroxyanilines and their metal complexes were described. The crystal and molecular structure of bis[2-hydroxy-4-propyloxy-N-(2-hydroxy-3,4-dipropyloxybenzylidene) aniline]copper(II) were determined by means of X-ray analysis. It crystallizes in the monoclinic space group P2(1)/n and a Z=4. The geometry at Cu2+ ions is square pyramidal with a THF solvent molecule coordinated. The core structure was nearly flat, and the intramolecular Cu–Cu atoms were separated by ca. 3.0163(6) Å. All compounds 2a formed smectic C phases, and copper complexes 1a–Cu were not mesogenic. In contrast, compound 2e and complexes 1b–Cu, 1d–Cu, 1e–Cu, and 1e–Pd exhibited columnar phases. The lack of mesomorphism in 1e–Zn was attributed to a preferred tetrahedral over square planar geometry. A Ncell equal to 2.44–2.92, calculated from powder XRD data within a 9.0 Å thick indicated that an induced structure correlated by two catenar-shaped molecules was formed in Colh phases.

Crystal structure of bis(α,α′-dithio-bis(formamidinium)) bis(μ2-chloro)hexachlorodimercurate(II)

The crystal and molecular structure of bis(α,α′-dithio-bis(formamidinium)) bis(μ2-chloro)hexachlorodimercurate(II) C4H16Hg2Cl8N8S4 (I), where α,α′-dithio-bis(formamidine) is C2H6N4S2, was solved. Crystals are monoclinic, a = 8.6417(6) A, b = 14.648(1) A, c = 10.2111(8) A, β = 104.949(1)°, V = 1248.8(2) A3, space group P21/n, Z = 4. The crystal structure is built of HgCl 4 2− ions linked via inversion centers into [Hg2Cl8]4− pairs and C2H8N4S 2 2+ cations. [Hg2Cl8]4− anions and C2H8N4S 2 2+ cations form alternating layers linked by N-H…Cl hydrogen bonds into a framework structure.

Anion‐π Interaction: An Influential Force in Solid State Molecular Microstructures

AbstractThe crystal structures of simple triphenyl(pentafluorobenzyl)phosphonium salts provide crucial data on the influence of anion size on the molecular structure of bis(pentafluorobenzyl)phosphonium cations containing two adjacent electron‐deficient moieties. Whereas the bromide anions interact by anion‐π interaction in a 1:1 mode with the pentafluorobenzene unit Z‐configured, the bulkier anions iodide, tetrafluoroborate, and hexafluorophosphate result in a 1:2 tweezer‐like anti‐configuration in which one anion interacts simultaneously with two pentafluorobenzene units. When spatial separation of the two electron‐deficient rings match the size of the anion, anion‐π interactions induce a conformational change from the anti‐form observed for the smaller anion to the tweezer‐like syn‐form.

Alkyl-substituted oxamide oximes and their metal complexes

Nickel(II) and palladium(II) complexes of oxamide oximes substituted with alkyl chains of different length (CnH2n+1, n=4, 6, 8, 10, 12 and 16) have been synthesized from the reaction of (E,E)-monochloroglyoxime with the corresponding amine derivatives. The Ni(II) and Pd(II) complexes have been prepared by reacting the ligand with either NiCl2·6H2O or Na2PdCl4 in ethanol. All the compounds were characterized by elemental analyses, 1H NMR, IR and mass spectra. The molecular structure of bis[(N-hexylaminoglyoxime)]palladium(II) (2b) was obtained by single crystal X-ray diffraction and it was found to be centrosymmetric at the metal center, which is bound by the four oximic nitrogen atoms of two ligands in a square planar environment. The role of the H-bonding in the structures of these complexes was investigated.

Synthesis, 2D NMR and X-ray diffraction studies on Cu(II) and Ni(II) complexes with ligands derived from azobenzene-cored Schiff base: Mesomorphic behaviors of Cu(II)–phenolates and crystal structure of bis[4-(4-alkoxy-2-hydroxybenzylideneamino)azobenzene]copper(II)

Two new homologous series of copper(II) and nickel(II) complexes derived from bidentate Schiff bases 4-(4-alkoxy-2-hydroxybenzylideneamino)azobenzene have successfully been synthesized. Their molecular structures were elucidated by FT-IR, 1H and 13C NMR along with 1H– 1H COSY, 1H– 13C HMQC, 1H and 13C HMBC. Mesomorphic behaviors of ligands and metal complexes have been investigated by differential scanning calorimetry and polarizing optical microscope. All ligands and their copper complexes exhibit exclusively the mesomorphic properties. The X-ray diffraction studies have confirmed the presence of smectic A (SmA) phase in copper(II)–phenolate complexes. The molecular structure of bis[4-(4-alkoxy-2-hydroxybenzylideneamino)azobenzene]copper(II) have been determined by using X-ray crystallographic techniques. It was found that the ligands have square planar configuration around the Cu center ion as evident by the N Cu N and O Cu O angles of 180°.

ChemInform Abstract: 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.

ChemInform Abstract: Molecular Geometry of Bis(N-chloromethyl)nitramine from Gas Electron Diffraction.

Abstract 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) A NN 1.422(5) A CN 1.443(4) A ClC 1.803(4) A CH 1.109(9) A 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 2 NNO 2 skeleton.