300 research outputs found
Bis(tripyrazol-1-ylmethane)nickel(II) tetracyanidonickelate(II) dihydrate
The title complex, [Ni(C10H10N6)2][Ni(CN)4]·2H2O, contains an octahedral nickel(II) cation and a square-planar nickel(II) anion. Both the cation and the anion reside on a crystallographic center of inversion. The NiII center in the cation is coordinated by six pyrazol-1-yl rings of two chelating tripyrazol-1-ylmethane [HC(pz)3] ligands, with Ni—N distances that range between 2.0647 (19) and 2.0828 (19) Å. The NiII center in the anion is coordinated by four cyanide ligands, with Ni—C distances in the range 1.869 (2)–1.869 (3) Å. The [Ni(CN)4]2− anions are linked by inversion-related water molecules into extended chains that run parallel to the a axis
Calibration of Multicurrency LIBOR Market Models
This paper presents a methodf or calibrating a multi currency lognormal LIBOR Market Model to market data of at-the-money caps, swaptions and FX options. By exploiting the fact that multivariate normal distributions are invariant under orthonormal transformations, the calibration problem is decomposed into manageable stages, while maintaining the ability to achieve realistic correlation structures between all modelled market variables.currency options; LIBOR market model; exchange rate risk; interest rate risk
5,5\u27-Dichloro-2,2\u27-dimethoxybiphenyl
In the title molecule, C14H12Cl2O2, the dihedral angle between the least-square planes of the benzene rings is 62.17 (6)°. Both methoxy groups are slightly out of the plane of the benzene rings to which they are attached, making dihedral angles of 4.22 (18) and 18.82 (16)°
2,2\u27,5\u27,6-Tetrachloro-4-[(1\u3cem\u3eS\u3c/em\u3e)-1-methylpropoxy]biphenyl
In the title molecule, C16H14Cl4O, the dihedral angle between the least-square planes of the benzene rings is 84.40 (7)°. No unusual intermolecular interactions are present
(11R)-13-Dimethylammonio-11,13-dihydro-4,5-epoxycostunolide semifumarate
Crystals of the title salt, C17H28NO3
+·C4H3O4
−, were obtained by reacting parthenolide with dimethylamine followed by conversion of the amine adduct into a water-soluble fumarate salt. Subsequent crystallization of the fumarate salt from water afforded colorless orthorhombic crystals. The amine addition is highly stereospecific yielding exclusively a single diastereomer with R-configuration at the newly formed C-11 chiral carbon. In the crystal, intermolecular O—H⋯O and N—H⋯O hydrogen bonds help to establish the packing
(Z)-3-(1-Benzofuran-2-yl)-2-(3,4,5-trimethoxyphenyl)acrylonitrile
In the title compound, C20H17NO4, the double bond of the acrylonitrile group separating the 1-benzofuran moiety from the 3,4,5-trimethoxyphenyl ring has Z geometry. The 1-benzofuran groups are π–π stacked with inversion-related counterparts such that the furan ring centroid–centroid distance is 3.804 (5) Å. The dihedral angle between the planes of the trimethoxyphenyl ring and the acrylonitrile group is 24.2 (2)°
Absolute Configuration of 2,2\u27,3,3\u27,6-Pentachlorinatedbiphenyl (PCB 84) Atropisomers
Nineteen polychlorinated biphenyl (PCB) congeners, such as 2,2′,3,3′,6-pentachlorobiphenyl (PCB 84), display axial chirality because they form stable rotational isomers, or atropisomers, that are non-superimposable mirror images of each other. Although chiral PCBs undergo atropselective biotransformation and atropselectively alter biological processes, the absolute structure of only a few PCB atropisomers has been determined experimentally. To help close this knowledge gap, pure PCB 84 atropisomers were obtained by semi-preparative liquid chromatography with two serially connected Nucleodex β-PM columns. The absolute configuration of both atropisomers was determined by X-ray single-crystal diffraction. The PCB 84 atropisomer eluting first and second on the Nucleodex β-PM column correspond to (aR)-(−)-PCB 84 and (aS)-(+)-PCB 84, respectively. Enantioselective gas chromatographic analysis with the β-cyclodextrin-based CP-Chirasil-Dex CB gas chromatography column showed the same elution order as the Nucleodex β-PM column. Based on earlier reports, the atropisomers eluting first and second on the BGB-172 gas chromatography column are (aR)-(−)-PCB 84 and (aS)-(+)-PCB 84, respectively. An inversion of the elution order is observed on the Cyclosil-B gas chromatography and Cellulose-3 liquid chromatography columns. These results advance the interpretation of environmental and human biomonitoring as well as toxicological studies
Substituted Pentacenes and Electronic Devices Made with Substituted Pentacenes
Novel substituted pentacenes and electronic devices made with those substituted pentacenes are disclosed
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