AbstractThe Title Compound Research Articles

The crystal and molecular structure of 1-ferrocenyl-3,3-bis(methylthio)prop-2-en-1-one

Abstract The title compound 1-ferrocenyl-3,3-bis(methylthio)prop-2-en-1-one (1), a key intermediate in the synthesis of ferrocene-containing heterocycles, has been characterized by single-crystal X-ray diffraction. Compound 1 crystallizes in the monoclinic space group P21/c with 8 molecules in the unit cell. Unit cell parameters are 12.8159(10), 10.8121(9), and 20.8411(16) Å for a, b and c, respectively with β = 98.985(4)°. There are two distinct molecules in the asymmetric unit (A and B). Both molecules display a nearly eclipsed conformation with respect to the individual intramolecular cyclopentadienyl units in addition to close intramolecular contacts between the carbonyl O atom and one S atom of the bis-methylthiol functionality. Close intermolecular contacts involving A and B are noted with respect to S⋯H interactions between a thiol-S and the substituted Cp group in addition to C=O∙∙∙HC= interactions with the ene-moiety and a H atom located on one of the thiomethyl groups.

Zur Kenntnis ternärer Oxoarsenate(III) dreiwertiger Lanthanoide: Synthese und Charakterisierung von LnAsO3- und Ln 2As4O9-Vertretern mit Ln = La und Ce sowie Ln = Pr, Nd, Sm–Gd

Abstract The title compounds have been prepared from the elemental lanthanoids and arsenic sesquioxide in 1:1 and 2:3 molar ratios in the presence of a cesium-halide flux at temperatures near 1000 °C generating elemental arsenic as the by-product. With the preparation of B-type La[AsO3] crystallizing in the monoclinic space group P21/c with the lattice parameters a = 904.03(8), b = 789.96(7), c = 837.49(7) pm and β = 103.354(3)°, both A- and B-type Ln[AsO3] representatives are now available for lanthanum and cerium. The crystal structure consists of two crystallographically distinct Ln 3+ cations with eight- or ninefold coordination by O2− anions. The Ln 3+ cations are arranged in layers of (Ln1)3+ and corrugated bilayers of (Ln2)3+ cations in the (100) plane. The two different As3+ cations appear in [AsO3]3− units, which differ mainly in their environment of Ln 3+ cations. The successful synthesis of the compounds Ln 2As4O9 (Ln = Pr, Nd, Eu and Gd) reported here on the one hand closes the structural gap between cerium and neodymium, and on the other hand also extends the spectrum of ternary oxoarsenates(III) of lanthanoids to gadolinium, with the neodymium compound for the first time at standard temperature. The crystals of the Ln 2As4O9 compounds are triclinic (space group: P 1 ‾ $P\overline{1}$ ) with lattice parameters nicely reflecting the lanthanoid contraction from a = 690.61(5), b = 768.95(6), c = 959.72(8) pm, α = 96.927(3), β = 103.812(3), γ = 104.441(3)° for Pr2As4O9 to a = 676.12(5), b = 751.58(6), c = 951.57(8) pm, α = 96.462(3), β = 103.678(3), γ = 104.409(3)° for Gd2As4O9 with two crystallographically independent lanthanoid(III) positions. The oxidic environments on these sites show the shape of square antiprisms with significant distortions, but (Ln2)3+ has a ninth oxygen contact in a capped antiprism. The linkage of the polyhedra creates layers in the ab plane, which are separated by the complex anions of arsenic. The oxoarsenate(III) units [AsO3]3− are linked by sharing oxygen corners to form both dinuclear [As2O5]4− and cyclic tetranuclear [As4O8]4− complex anions, which is why the compounds can also be represented with their structured molecular formula Ln 4[As2O5]2[As4O8]. The free electron pairs of the arsenic(III) cations point into channels, which are built up in the crystal structure along [010].

Structure and properties of two new heteroleptic bismuth(III) dithiocabamates of the general composition Bi(S2CNH2)2X (X = Cl, SCN)

Abstract The title compounds were prepared by precipitation from acidic solutions of the reactants in acetone/water. Bi(S2CNH2)2Cl (1) crystallizes in the non-centrosymmetric trigonal space group P32 with a = 8.6121(3) and c = 11.1554(4) Å, Z = 3; Bi(S2NH2)2SCN (2) in P21/c (monoclinic) with a = 5.5600(2), b = 14.3679(5), c = 12.8665(4) Å, and β = 90.37(3)°. In the crystal structure of 1 Bi3+ is in a sevenfold coordination of two bidentate and one monodentate S2CHNH2 − anions with an asymmetric coordination pattern of five Bi–S and two Bi–Cl− bonds. The linkage of these polyhedra via common Cl–S edges leads to a 1D polymeric structure with undulated chains propagating in the direction [001]. These chains are linked by strong and medium strong hydrogen bonds forming the 3D crystal structure. In the crystal structure of 2 the Bi3+ cation is in an eightfold coordination. The polyhedron can be described as a significantly distorted tetragonal anti-prism, capped by an additional S atom. Two of these prisms share a common quadrilateral face to form a “prism-double” (Bi2S10N2). These building units are linked by common edges, and the resulting 1D infinite angulated chains propagate along [100]. By contrast to organo-dithiocarbamate compounds, where C–H···X bridges are dominant, the interchain connections in the crystal structures of 1 and 2 are formed exclusively via N–H···S, N–H···Cl, and N–H···N interactions, generating the 3D networks. A significant eccentricity of the Bi3+ cation in the crystal structures of both complexes is observed. Both compounds emit light in the orange range of the electromagnetic spectrum.

Crystal and electronic structure of the new ternary phosphide Ho5Pd19P12

Abstract The title compound was prepared from the pure elements by sintering. The crystal structure was investigated by means of powder X-ray diffraction data. Ho5Pd19P12 exhibits the hexagonal Ho5Ni19P12-type structure with space group P 6 ‾ 2 m $P‾{6}2m$ , a = 13.1342(2), c = 3.9839(1) Å, R I = 0.060, R p = 0.080. The crystal structure can be described as a combination of two types of the structural units, [HoPd6P3] and [Ho3Pd10P6], respectively, mutually displaced by 1/2 along the crystallographic c axis. Quantum chemical calculations have been performed to analyze the electronic structure and provide deeper insight into the structure-property relationships. The results of the quantum chemical calculations indicate that the material features metallic bonding between Ho and Pd and covalent bonding between Pd and P.

ErNi2.23Al2.77 and YbNi2.31Al2.69 – i3 superstructures of the CaCu5 type

Abstract The title compounds have been synthesized by reaction of the elements in sealed tantalum crucibles in a muffle furnace using special annealing sequences. The crystal structures of YbNi2.31Al2.69 (R1 = 0.0100 for 212 F 2 values and 18 variables) and for ErNi2.23Al2.77 (R1 = 0.0154 for 255 F 2 values and 18 variables) were refined from single crystal X-ray data. They belong to the YNi2Al3 type (i3 superstructure of CaCu5) with the following crystallographic parameters: space group P 6 / m m m $P6/mmm$ , Pearson symbol hP18, Z = 3, a = 8.2723(12), c = 4.0672(8) Å, V = 241.03(8) Å3 for YbNi2.31Al2.69 and a = 8.9109(13), c = 4.0669(8) Å, V = 279.66(8) Å3 for ErNi2.23Al2.77. The crystal chemical discussion is supported by electronic structure calculations.

Theoretical and experimental solid state studies of Ethyl 1-benzyl-2-(thiophen-3-yl)-1H-benzo[d]imidazole-5-carboxylate

Abstract The title compound Ethyl 1-benzyl-2-(thiophen-3-yl)-1H-benzo[d]imidazole-5-carboxylate (BI) is prepared and characterized using spectroscopic methods. The theoretical optimization and three dimensional molecular structure are confirmed by X-ray diffraction method (single crystal). The C–H…π intermolecular interactions stabilize the crystal structure. The intermolecular contacts in the crystal structure are quantified using Hirshfeld surfaces and the crystal packing is elucidated using 3D energy frameworks analysis. In the frameworks, the dispersion energy term is dominated over the electrostatic energy term. The structural optimization was carried out with B3LYP/6-311++G (d, p) level of theory. The visual representations of positive and negative potentials (electrostatic potential) are mapped on the electron density isosurface. The band gap energy (HOMO-LUMO) of the molecule is calculated to be 4.36 eV. Structural conformation of BI is compared with similar structures.

Synthesis, properties and crystal structure of novel Copper(II) ammine complex with [Pd(CN)4]2− building blocks

Abstract The title compound [Cu4(NH3)12-(µ2-CN)8-Pd4(CN)8] was prepared from the aqueous solution Cu2+ – N,N,N′,N′-tetraethylethane-1,2-diamine – [Pd(CN)4]2−, where the addition of excess amounts of ammonia caused the dissolution of the precipitate formed during reaction. Using this method, we prepared and structurally characterized the new complex of Cu(II) containing ammine ligand with tetracyanidopalladate(II) anion incorporated within the molecule. The crystal structure of compound is molecular; the unit cell contains centrosymmetric octanuclear molecules in which all central atoms lies on mirror plane. Generally, the structure of the molecule can be divided into central cyclic part and terminal pendants. The structure contains nitrogen atoms derived from the ammonia molecules coordinated to Copper(II) atoms. They are involved in the formation of N-H···N hydrogen bonds type.

Diethyl (iodoethynyl)phosphonate and (iodoethynyl)diphenylphosphane oxide: crystal structures and some cycloaddition reactions

Abstract The title compounds are difunctionalized acetylenic building blocks, which can serve as electrophilic dienophiles and dipolarophiles in [4+2] and azide-iodoalkyne [3+2] cycloaddition reactions, which, however, require strong thermal activation. In their crystal structures, they are self-complementary tectons, which are arranged in polymeric chains maintained by very short intermolecular Csp–I···O=P halogen bonds.

A new ternary silicide GdFe1− x Si2 (x=0.32): preparation, crystal and electronic structure

Abstract The title compound was prepared from the elements by arc-melting. The crystal structure was investigated by means of single-crystal X-ray diffraction. It crystallizes in the TbFeSi2 structure type, orthorhombic space group Cmmm, a = 4.0496(8), b = 16.416(2), c = 3.9527(6) Å, Z = 4, R1 = 0.041, wR2 = 0.11 for 207 unique reflections with I o > 2 σ(I o) and 19 refined parameters. The Fe position is not fully occupied and the refinement results in a composition GdFe0.68Si2 in agreement with a chemical analysis. The structure consists of zig-zag chains of Si(1) atoms which are terminally bound to additional Si(2) atoms. For an ordered variant GdFe0.5Si2 the Zintl concept can be applied which results in formal oxidation states Gd3+(Fe2+)0.5Si(1)1−Si(2)3−. The electronic structure of this variant GdFe0.5Si2 was analyzed using the tight-binding LMTO method and the results confirm the simple bonding picture.

β-Eu(BO2)3 – a new member of the β-RE(BO2)3 (RE=Y, Nd, Sm, Gd–Lu) structure family

Abstract The title compound β-Eu(BO2)3 was synthesized in a high-pressure/high-temperature experiment at 4 GPa and 1473 K. The europium borate crystallizes in the orthorhombic space group Pnma (no. 62) with the lattice parameters a = 16.071(2), b = 7.440(4), and c = 12.362(5) Å. The structure is isotypic to the already known meta-borates β-RE(BO2)3 (RE = Y, Nd, Sm, Gd, Dy–Lu) and is built up of approximately triangular ribbons of BO4 tetrahedra. The compound was further characterized by X-ray powder diffraction, vibrational spectroscopy and shows a typical Eu3+ line emission upon excitation at 448 nm.

Crystal, molecular and electronic structure of (5S,11R,11aS)-11-hydroxy-5-methyl-1,2,3,4,5,6,11,11a-octahydropyrido[1,2-b]isoquinolin-5-ium iodide

Abstract The title compound, C14H20INO, is a molecule with three stereogenic centres. It absolute configuration was derived from the synthesis and confirmed by structure determination (AD, Flack (Parsons’) parameter: 0.031 (8)). The expected stereochemistry of atoms N1 was confirmed to be S, C5 was confirmed to S, C6 was confirmed to R. The central N-heterocyclic ring is not planar and adopts a half-chair conformation. A calculation of least-squares planes showed that these rings are puckered in such a manner that the five atoms: C5, C6, C7, C12 and C13 (the second ring: C1, C2, C3, C4, C5 and N1) are planar, while atom N1 is displaced from these plane with the out-of-plane displacement of −0.694 (4) and −0.670 (5) Å in the second ring, respectively. Dihedral angle between the planes of the central N-heterocyclic rings is 23.4 (2)°. Crystal structure is also stabilized by C—H···O hydrogen interactions.

Synthesis and antimicrobial activity of 3,4-dihydropyrimidin-2(1H)-one derivatives containing a hydrazone moiety

Abstract The title compounds were synthesized and characterized by IR, 1H NMR, 13C NMR and HRMS data. Their antimicrobial activities against bacterial strains Escherichia coli and fungal strains Aspergillus niger were evaluated.

Solvent-free preparation of 3-aryl-2-[(aryl)(arylamino)]methyl-4H-furo[3,2-c]chromen-4-one derivatives using ZnO-ZnAl2O4 nanocomposite as a heterogeneous catalyst

Abstract The title compounds were synthesized by a three-component reaction of 4-hydroxycoumarin, aromatic amines and α,β-epoxy ketones, catalyzed by ZnO-ZnAl2O4 nanocomposite.

A new solid solution compound with the Sr21Mn4Sb18 structure type: Sr13Eu8Cd3Mn1Sb18

Abstract The title compound with the nominal formula, Sr13Eu8Cd3Mn1Sb18, was synthesized by Sn-flux. Structure refinement was based on single-crystal X-ray diffractometer data. Employing the exact composition, the formula is Sr13.23Eu7.77Cd3.12Mn0.88Sb18 for the solid solution Sr21-xEuxCd4-yMnySb18. This phase adopts the Sr21Mn4Sb18 type structure with site preferences for both Eu and Cd. The structure crystallizes in the monoclinic system in space group C2/m and Z=4: a=18.1522(11), b=17.3096(10), c=17.7691(10) Å, β=91.9638(8)°, 6632 F2 values, 216 variables, R1=0.0254 and wR2=0.0563. Site selectivity of the elements in this new compound will be discussed in relationship with the Sr21Mn4Sb18 type structure and other related structure types. Temperature dependent magnetic susceptibility data reveal Curie–Weiss paramagnetism with an experimental moment of 19.3 μB/f.u. and a Weiss constant of 0.4 K. Magnetic ordering is seen at low temperatures, with a transition temperature of 3.5 K.

Crystal and molecular structure of 1-picryl-2-phenyl-2-(4-picrylamidophenyl)-diazenium betaine: analogy between a picramido group and an oxygen atom

Abstract The title compound is formed by a non-trivial reaction involving two molecules of the stable free radical 2,2-diphenyl-1-picryl-hydrazyl and one molecule of N-methoxy-picramide. We could now perform an X-ray diffraction experiment on a single crystal and can fully confirm the betaine structure which has a central quinonoid ring with alternating long and short bonds.

Invariom-based comparative electron density studies of iso-sildenafil and sildenafil

Abstract The title compounds have raised considerable medical and broad public interest in that sildenafil is used as an agent against male erectile dysfunction; iso-sildenafil is not in clinical use. A comparison of their structural and electronic properties therefore seems of interest. The electron densities of iso-sildenafil and the cationic and neutral forms of sildenafil were examined by the application of the invariom formalism relying on diffraction data reported in the literature. The electron-density distributions obtained were subjected to topological analysis using the quantum theory of atoms in molecules (QTAIM) formalism to yield bond topological and atomic properties. Moreover, molecular Hirshfeld surfaces and electrostatic potentials (ESPs) were calculated. A number of structural and electronic differences were thus identified between sildenafil and the iso-analog. In both sildenafil structures, the phenyl ring and the pyrazolopyrimidine fragment are practically coplanar (planar conformation), whereas in the iso-analog they exhibit an angle of 44° (inclined form). Related to differences in molecular structure are completely different hydrogen bonding patterns and differences in the ESPs, the latter ones being influenced by different methylation at the pyrazolopyrimidine fragment. Iso-sildenafil is present as a hydrogen-bond dimer in the crystal, and the ESP of this dimer is dominated by a surrounding positive potential.

Spectroscopic, Quantum Chemical, Physical and Antioxidant Studies on 2-Amino 4-Picolinium 4-Nitrobenzoate – An Organic Crystal for Nonlinear Optical and Biological Applications

AbstractThe title compound, 2-amino 4-picolinium 4-nitrobenzoate (2A4PNB), has been identified as a nonlinear optical material and its good quality single crystals were grown from methanol solution. It crystallizes in monoclinic system with the non-centro symmetric space groupPc. Its structure and chemical compositions were confirmed by the X-ray diffraction and microanalysis studies, respectively. FTIR, UV-Visible-NIR, NMR and photoluminescence (PL) spectra have been recorded and extensive spectroscopic investigations have been carried out. The grown crystals have been subjected to micro hardness and photoconductivity studies to explore its physico chemical properties. The free radical scavenging activity of the complex has been determined against DPPH and H2O2radicals. In addition, the quantum chemical studies were performed on the isolated 2A4PNB molecule using DFT calculations at the B3LYP/6-311++G (d,p) basis set.

Crystal and molecular structure of (9aS,10S)-6-Oxo-6,7,8,9,9a,10-hexahydro-4H-thieno-[2,3-b]quinolizin-10-yl acetate

Abstract The title compound, C13H15NO3S, is a chiral molecule with two stereogenic centres. Its absolute configuration was derrived from the synthesis and confirmed by structure determination. The expected stereochemistry of atoms C5 and C6 was confirmed to be S. The central N-heterocyclic rings are not planar and adopt a half-chair conformation. A calculation of least-squares planes showed that these rings are puckered in such a manner that the five atoms C1, C2, C3, C5 and N1 (second ring: N1, C6, C7, C10 and C11) are planar, while atoms C4 (C5) are displaced from these planes with the out-of-plane displacement of 0.582 (3) Å and 0,666 (2) Å in the second ring, respectively. Dihedral angle between the planes of the central N-heterocyclic rings is 40.0 (1)°. Crystal structure is stabilized by C—H···O hydrogen interactions.

Crystal structure of (E)-4-nitro-2-(((3-(tetrahydro-8λ4-[1,3,2]oxazaborolo[2,3-b][1,3,2]oxaborol-8-yl)phenyl)imino)methyl)phenol – water (1/2), C17H18BN3O5·2H2O

Abstract The title compound has been synthesized and characterized by IR, 1H NMR, elemental analysis as well as single crystal X-ray diffraction techniques. Crystal structure analysis reveals that the boron atom is tetrahedrally bonding with one carbon atom, one nitrogen atom, and two oxygen atoms. The bond between nitrogen atom and boron atom is a coordination bond.

Tl2C2O4·H2C2O4: a new crystalline form of thallium(I) oxalate

Abstract The title compound was prepared by reaction, in aqueous solution, of Tl2CO3 and H2C2O4·2H2O in a molar ratio of 1:2. Its crystal structure was solved by X-ray diffraction methods. It crystallizes in the monoclinic space group P21/a with Z = 2 molecules per unit cell. The oxalic acid molecule and the oxalate anion are planar, residing on crystallographic inversion centers, and linked to each other by strong O–H···O hydrogen bonds giving rise to a polymeric structure. The Tl(I) ion is in a distorted polyhedral coordination with nine neighboring O atoms, five of oxalate anions and four others of oxalic acid molecules. The FTIR and FT-Raman spectra of the compound were also recorded and are briefly discussed.