6,498 results match your criteria Acta Crystallographica Section C-Crystal Structure Communications[Journal]


Intermolecular C-H···O, Cl···Cl and π-π interactions in the 2-dichloromethyl derivative of vitamin K3.

Acta Crystallogr C 2013 Dec 30;69(Pt 12):1563-6. Epub 2013 Nov 30.

Istituto di Scienze e Tecnologie Molecolari, Consiglio Nazionale delle Ricerche, Via C. Golgi, 19, I-20133 Milano, Italy.

The title 1,4-naphthoquinone, 2-dichloromethyl-3-methyl-1,4-dihydronaphthalene-1,4-dione, C12H8Cl2O2, is a chlorinated derivative of vitamin K3, which is a synthetic compound also known as menadione. Molecules of (I) are planar and lie on a crystallographic mirror plane (Z' = 0.5) in the space group Pnma. Read More

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December 2013

Isolation, pharmacological activity and structure determination of physalin B and 5β,6β-epoxyphysalin B isolated from Congolese Physalis angulata L.

Acta Crystallogr C 2013 Dec 30;69(Pt 12):1557-62. Epub 2013 Nov 30.

Chemistry Department, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven (Heverlee), Belgium.

Physalis angulata L., an annual herb from the Solanaceae family, is widely used in popular medicine in tropical countries to treat a variety of diseases. Two products, (X) and (Y), were isolated from a crude CH2Cl2 extract of dried Congolese Physalis angulata L. Read More

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December 2013

Transannular S···N interactions in 10-ethynyl-10H-phenothiazine 5-oxide and 5,5-dioxide.

Acta Crystallogr C 2013 Dec 30;69(Pt 12):1553-6. Epub 2013 Nov 30.

Department of Material Science and Chemistry, Wakayama University, Sakaedani, Wakayama 640-8510, Japan.

The title compounds, C14H9NOS, (1), and C14H9NO2S, (2), are oxidation products of the parent compound 10-ethynyl-10H-phenothiazine. They differ with respect to transannular interactions, the intramolecular S···N contact being shorter in (2). Intermolecular Csp-H···O hydrogen bonds were detected in both crystals, and (1) was found to form stronger hydrogen bonds. Read More

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December 2013

Two polymorphs of 2-ethyl-3-hydroxy-6-methylpyridinium hydrogen N-acetyl-L-glutamate from powder diffraction data.

Acta Crystallogr C 2013 Dec 30;69(Pt 12):1549-52. Epub 2013 Nov 30.

Department of Chemistry, M.V. Lomonosov Moscow State University, 119991 Moscow, Russian Federation.

The title salt, C8H12NO(+)·C7H10NO5(-), crystallizes in two polymorphic modifications, viz. monoclinic (M) and orthorhombic (O). The crystal structures of both polymorphic modifications have been established from laboratory powder diffraction data. Read More

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December 2013

Three-dimensional hydrogen-bonded assembly in 2,2'-disulfanylidene-5,5'-biimidazolidinylidene-4,4'-dione-dimethylformamide-water (3/2/4).

Authors:
De-Hong Wu

Acta Crystallogr C 2013 Dec 21;69(Pt 12):1545-8. Epub 2013 Nov 21.

College of Chemistry and Chemical Engineering, Southeast University, Nanjing 210096, People's Republic of China.

The title compound, 3C6H4N4O2S2·2C3H7NO·4H2O, comprises three 2,2'-disulfanylidene-5,5'-biimidazolidinylidene-4,4'-dione molecules, two dimethylformamide molecules and four water molecules arranged around a crystallographic inversion centre. The non-H atoms within the 5,5'-biimidazolidinylidene molecule are coplanar and these molecules aggregate through N-H···S hydrogen-bonding interactions with cyclic motifs [graph set R2(2)(8)], giving two-dimensional ribbon structures which are close to being parallel. The two independent water molecules associate to form centrosymmetric cyclic hydrogen-bonded (H2O)4 tetrameric units [graph set R4(4)(8)]. Read More

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December 2013

Head-to-tail square-shaped cyclic hydrogen bonds leading to dimeric aggregates: 1,8-dibenzoyl-2,7-dihydroxynaphthalene and a comparison with its analogous benzoylnaphthalene.

Acta Crystallogr C 2013 Dec 21;69(Pt 12):1541-4. Epub 2013 Nov 21.

Department of Organic and Polymer Materials Chemistry, Tokyo University of Agriculture & Technology (TUAT), Koganei, Tokyo 184-8588, Japan.

The title compound, C24H16O4, crystallized with two independent molecules in the asymmetric unit. Both carbonyl groups in these molecules form intramolecular O-H.. Read More

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December 2013

Two-dimensional hydrogen-bonded supramolecular networks in the compounds of benzene-1,2,4,5-tetracarboxylic acid (pyromellitic acid) with 2,2'-biimidazole and 4,4'-dimethyl-2,2'-bipyridine.

Authors:
Kai-Long Zhong

Acta Crystallogr C 2013 Dec 15;69(Pt 12):1537-40. Epub 2013 Nov 15.

Department of Applied Chemistry, Nanjing College of Chemical Technology, Nanjing 210048, People's Republic of China.

Two products from the proton-transfer reactions of benzene-1,2,4,5-tetracarboxylic acid (pyromellitic acid, PMA) with 2,2'-biimidazole and 4,4'-dimethyl-2,2'-bipyridine, namely 2,2'-biimidazole-3,3'-diium 2,5-dicarboxybenzene-1,4-dicarboxylate, C6H8N4(2+),C10H4O8(2-), (I), and 4-methyl-2-(4-methylpyridin-2-yl)pyridinium 2,4,5-tricarboxybenzoate monohydrate, C12H13N2(+)·C10H5O8(-)·H2O, (II), have been prepared and their structures determined. Both compounds crystallize in the space group P1. The asymmetric unit of (I) is composed of two independent ion pairs. Read More

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December 2013

Imidazolidin-2-one: pseudosymmetry and twinning.

Acta Crystallogr C 2013 Dec 15;69(Pt 12):1534-6. Epub 2013 Nov 15.

Institute of Inorganic and Analytical Chemistry, Technical University of Braunschweig, Hagenring 30, D-38106 Braunschweig, Germany.

The title compound, C3H6N2O, crystallizes with imposed twofold symmetry in the space group I4(1)/a. The five-membered ring displays a half-chair conformation. N-H···O hydrogen bonds connect the molecules to form R2(2)(8) rings and thence ribbons parallel to the a and b axes. Read More

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December 2013

4-Oxo-N-phenyl-4H-chromene-2-carboxamide and of a new polymorph of 7-methoxy-4-oxo-N-p-tolyl-4H-chromene-2-carboxamide and its hemihydrate.

Acta Crystallogr C 2013 Dec 13;69(Pt 12):1527-33. Epub 2013 Nov 13.

CIQ/Departamento de Quιmica e Bioquιmica, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, Portugal.

4-Oxo-N-phenyl-4H-chromene-2-carboxamide, C16H11NO3, crystallizes in the space group P2(1)/n and its derivative 7-methoxy-4-oxo-N-p-tolyl-4H-chromene-2-carboxamide, C18H15NO4, forms two polymorphs which crystallize in the space groups P2(1)/c and P1. The structures have an anti-rotamer conformation about the C-N bond; however, the amide O atom can be either trans- or cis-related to the O atom of the pyran ring. The latter compound also crystallizes as a hemihydrate, C18H15NO4·0. Read More

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December 2013

(9E)-9-benzylidene-2-methylsulfanyl-5-phenyl-6,7,8,9-tetrahydropyrimido[4,5-b]quinolin-4(3H)-one: a hydrogen-bonded R2(2)(8) dimer.

Acta Crystallogr C 2013 Dec 13;69(Pt 12):1524-6. Epub 2013 Nov 13.

Departamento de Química, Universidad de Valle, AA 25360 Cali, Colombia.

In the molecule of the title compound, C25H21N3OS, which was prepared by mild oxidation of the corresponding 5,6,7,8,9,10-hexahydro analogue, the fused carbocyclic ring adopts an envelope conformation. Pairs of molecules are linked into cyclic centrosymmetric dimers by pairs of inversion-related N-H···O hydrogen bonds. Read More

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December 2013

Tosylate salts of the anticancer drug lapatinib.

Acta Crystallogr C 2013 Dec 8;69(Pt 12):1516-23. Epub 2013 Nov 8.

Centre for X-ray Crystallography, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India.

Two tosylate salts of an anticancer drug lapatinib, viz. a monotosylate [systematic name: ({5-[4-({3-chloro-4-[(3-fluorophenyl)methoxy]phenyl}amino)quinazolin-6-yl]furan-2-yl}methyl)[2-(methylsulfonyl)ethyl]azanium 4-methylbenzenesulfonate], C29H27ClFN4O4S(+)·C7H7O3S(-), (I), and a ditosylate [systematic name: 4-({3-chloro-4-[(3-fluorophenyl)methoxy]phenyl}amino)-6-]5-({[2-(methylsulfonyl)ethyl]azaniumyl}methyl)furan-2-yl[quinazolin-1-ium bis(4-methylbenzenesulfonate)], C29H28ClFN4O4S(2+)·2C7H7O3S(-), (II), were obtained during crystallization attempts for polymorphism. In both structures, the lapatinib cation is in a distorted U-like conformation and the tosylate anion is clamped between the aniline N atom and methylamine N atom through N-H···O hydrogen bonds, forming an R2(2)(15) ring motif. Read More

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December 2013

4,4'-{Diazenediylbis[(1,4-phenylene)bis(carbonyloxy)]}bis(2,2,6,6-tetramethylpiperidinyloxidanyl): the first crystal structure determination from powder data of a nitroxide radical.

Acta Crystallogr C 2013 Dec 8;69(Pt 12):1513-5. Epub 2013 Nov 8.

Institute of Inorganic and Analytical Chemistry, Goethe University, Max-von-Laue-Strasse 7, D-60438 Frankfurt am Main, Germany.

The title compound, C32H42N4O6, is a novel nitroxide radical used for pulsed electron-electron double resonance (PELDOR) spectroscopy. Its crystal structure was determined from laboratory X-ray powder diffraction data. The attractive forces between the molecules in the crystal structure are mainly of dispersive nature. Read More

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December 2013

A polymorphic form of 4,4-dimethyl-8-methylene-3-azabicyclo[3.3.1]non-2-en-2-yl 3-indolyl ketone, an indole alkaloid extracted from Aristotelia chilensis (maqui).

Acta Crystallogr C 2013 Dec 8;69(Pt 12):1509-12. Epub 2013 Nov 8.

Laboratorio de Química de Productos Naturales, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Casilla 160, Concepción, Chile.

The title compound [systematic name: (4,4-dimethyl-8-methylene-3-azabicyclo[3.3.1]non-2-en-2-yl)(1H-indol-3-yl)methanone], C20H22N2O, (II), was obtained from mother liquors extracted from Aristotelia chilensis (commonly known as maqui), a native Chilean tree. Read More

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December 2013

Novel three-dimensional coordination polymers of lanthanides with sulfate and oxydiacetic acid.

Acta Crystallogr C 2013 Dec 30;69(Pt 12):1503-8. Epub 2013 Nov 30.

School of Chemistry, University of Hyderabad, Hyderabad 500 046, India.

Three three-dimensional coordination polymers, viz. poly[[diaqua-μ4-oxydiacetato-di-μ4-sulfato-dipraseodymium(III)] hemihydrate], [Pr2(C4H4O5)(SO4)2(H2O)2]·0.5H2O, (I), poly[[diaquadi-μ3-oxydiacetato-μ3-sulfato-dineodymium(III)] 1. Read More

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December 2013

Supramolecular architecture of metal-organic frameworks involving dinuclear copper paddle-wheel complexes.

Acta Crystallogr C 2013 Dec 30;69(Pt 12):1498-502. Epub 2013 Nov 30.

School of Chemistry, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu, India.

The two centrosymmetric dinuclear copper paddle-wheel complexes tetrakis(μ-4-hydroxybenzoato-κ(2)O:O')bis[aquacopper(II)] dimethylformamide disolvate dihydrate, [Cu2(C7H5O3)4(H2O)2]·2C3H7NO·2H2O, (I), and tetrakis(μ-4-methoxybenzoato-κ(2)O:O')bis[(dimethylformamide-κO)copper(II)], [Cu2(C8H7O3)4(C3H7NO)2], (II), crystallize with half of the dinuclear paddle-wheel cage unit in the asymmetric unit and, in addition, complex (I) has one dimethylformamide (DMF) and one water solvent molecule in the asymmetric unit. In both (I) and (II), two Cu(II) ions are bridged by four syn,syn-η(1):η(1):μ carboxylate groups, showing a paddle-wheel cage-type structure with a square-pyramidal coordination geometry. The equatorial positions of (I) and (II) are occupied by the carboxylate groups of 4-hydroxy- and 4-methoxybenzoate ligands, and the axial positions are occupied by aqua and DMF ligands, respectively. Read More

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December 2013

Calcium and strontium salts of (glycinato-κ(2)N,O)oxidobis(peroxido-κ(2)O,O')vanadate(V) tetrahydrate.

Acta Crystallogr C 2013 Dec 30;69(Pt 12):1494-7. Epub 2013 Nov 30.

Department of Material Science and Chemistry, Faculty of Systems Engineering, Wakayama University, 930 Sakaedani, Wakayama 640-8510, Japan.

The title salts calcium (glycinato-κ(2)N,O)oxidobis(peroxido-κ(2)O,O')vanadate(V) tetrahydrate, Ca[VO(O2)2(NH2CH2COO)]·4H2O, and strontium (glycinato-κ(2)N,O)oxidobis(peroxido-κ(2)O,O')vanadate(V) tetrahydrate, Sr[VO(O2)2(NH2CH2COO)]·4H2O, crystallized at pH ca 7.4 with similar lattice parameters. The glycinate anion acts as a bidentate N,O-chelating ligand, and the V atom has a pentagonal bipyramidal geometry, with two η(2)-peroxo groups and the glycinate N atom in the equatorial plane, and one terminal oxo and a glycinate O atom at the axial positions. Read More

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December 2013

The coordination chemistry of two symmetric fluorene-based organic ligands with cuprous chloride.

Acta Crystallogr C 2013 Dec 21;69(Pt 12):1488-93. Epub 2013 Nov 21.

College of Chemistry, Chemical, Engineering and Materials Science, Shandong Normal University, Jinan 250014, People's Republic of China.

Two novel symmetric fluorene-based ligands, namely, 2,7-bis(1H-imidazol-1-yl)-9,9-dimethyl-9H-fluorene [L1 or (I), C21H18N4] and 2,7-bis(1H-imidazol-1-yl)-9,9-dipropyl-9H-fluorene (L2), have been used to construct the coordination polymers catena-poly[[dichloridodicopper(I)(Cu-Cu)]-μ-2,7-bis(1H-imidazol-1-yl)-9,9-dimethyl-9H-fluorene], [Cu2Cl2(C21H18N4)]n, (II), and catena-poly[[tetra-μ2-chlorido-tetracopper(I)]-bis[μ-2,7-bis(1H-imidazol-1-yl)-9,9-dipropyl-9H-fluorene]], [Cu4Cl4(C25H26N4)2]n, (III). There are three types of C-H···N hydrogen bonds in (I), resulting a two-dimensional network in the ab plane, including a chiral helical chain along the b axis. Compounds (II) and (III) are related one-dimensional polymers. Read More

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December 2013

A three-dimensional chiral crystal structure constructed from a chiral triazolate ligand showing an SrSi2 topology: poly[bis(μ3-3,5-diethyl-1,2,4-triazolato-κ(3)N(1):N(2):N(4))trisilver nitrate].

Acta Crystallogr C 2013 Dec 13;69(Pt 12):1485-7. Epub 2013 Nov 13.

School of Pharmacy, China Pharmaceutical University, Nanjing 211198, People's Republic of China.

In the title metal-organic framework (MOF), {[Ag3(C6H10N3)2]NO3}n, the Ag(I) cation is coordinated by two N atoms from two different 3,5-diethyl-1,2,4-triazolate (detz) ligands in a linear configuration. Each Ag(I) cation is then connected to two adjacent Ag(I) cations via a μ3-N(1):N(2):N(4)-detrz ligand, resulting in a three-dimensional chiral silver-triazolate structure showing an SrSi2 (srs) net with 10(3) topology. Read More

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December 2013

(OC-6-13)-difluoridooxidobis(propan-2-ol)(propan-2-olato)vanadium(V).

Acta Crystallogr C 2013 Dec 8;69(Pt 12):1482-4. Epub 2013 Nov 8.

Institut für Chemie, Technische Universität Berlin, Straße des 17 Juni 135, 10623 Berlin, Germany.

The distorted octahedral title complex, [V(V)(C3H7O)(C3H8O)2F2O], was synthesized via ligand exchange at [V(V)O(OiPr)3] with aqueous hydrogen fluoride in propan-2-ol and crystallized from (D)chloroform at 238 K after a few weeks. Crystal structure determination shows two C1-symmetric moieties to be present in the asymmetric unit, forming infinite chains along [100] via hydrogen bonds. The compound provides the first crystal structure containing the [VF2O(OiPr)] motif. Read More

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December 2013

A two-dimensional Cu(I) framework incorporating the 1-phenyl-1H-1,2,3,4-tetrazole-5-thiol ligand.

Acta Crystallogr C 2013 Dec 8;69(Pt 12):1478-81. Epub 2013 Nov 8.

Key Laboratory of Inorganic Chemistry in Universities of Shandong, Department of Chemistry and Chemical Engineering, Jining University, Qufu, Shandong 273155, People's Republic of China.

The new two-dimensional coordination polymer, poly[(μ4-1-phenyl-1H-1,2,3,4-tetrazole-5-thiolato)copper(I)], [Cu(C7H5N4S)]n, has been prepared under solvothermal conditions by reacting CuBr with 1-phenyl-1H-1,2,3,4-tetrazole-5-thiol (Hptt) in an acetonitrile and acetone solution. In the crystal structure, each Cu(I) ion is coordinated by two N atoms and two S atoms from four ptt(-) ligands, and each ptt(-) ligand links four Cu(I) ions to form two-dimensional layers which lie parallel to the (100) plane. These layers stack along the [100] direction via van der Waals interactions. Read More

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December 2013

Coordination polymeric structures in the sodium salt of 4-chloro-3-nitrobenzoic acid and the sodium and potassium salts of 4-nitroanthranilic acid.

Authors:
Graham Smith

Acta Crystallogr C 2013 Dec 8;69(Pt 12):1472-7. Epub 2013 Nov 8.

Science and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia.

The structures of the hydrated sodium salts of 4-chloro-3-nitrobenzoic acid {poly[aqua(μ4-4-chloro-3-nitrobenzoato)sodium(I)], [Na(C7H3ClNO4)(H2O)]n, (I)} and 2-amino-4-nitrobenzoic acid {poly[μ-aqua-aqua(μ3-2-amino-4-nitrobenzoato)sodium(I)], [Na(C7H5N2O4)(H2O)2]n, (II)}, and the hydrated potassium salt of 2-amino-4-nitrobenzoic acid {poly[μ-aqua-aqua(μ5-2-amino-4-nitrobenzoato)potassium(I)], [K(C7H5N2O4)(H2O)]n, (III)} have been determined and their complex polymeric structures described. All three structures are stabilized by intra- and intermolecular hydrogen bonding and strong π-π ring interactions. In the structure of (I), the distorted trigonal bipyrimidal NaO5 coordination polyhedron comprises a monodentate water molecule and four bridging carboxylate O-atom donors, generating a two-dimensional polymeric structure lying parallel to (001). Read More

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December 2013

Distorted octahedral environments in tricarbonylrhenium(I) complexes of 5-[2-(2,4,6-trimethylphenyl)diazen-1-yl]quinolin-8-olate and 5,7-bis[2-(2-methylphenyl)diazen-1-yl]quinolin-8-olate.

Acta Crystallogr C 2013 Dec 8;69(Pt 12):1467-71. Epub 2013 Nov 8.

Department of Chemistry, University of the Free State, PO Box 339, Bloemfontein 9300, South Africa.

The Re(I) centres of two Re(I)-tricarbonyl complexes, viz. tricarbonyl(pyridine-κN){5-[2-(2,4,6-trimethylphenyl)diazen-1-yl]quinolin-8-olato-κ(2)N(1),O}rhenium(I), [Re(C23H21N4O)(CO)3], (I), and {5,7-bis[2-(2-methylphenyl)diazen-1-yl]quinolin-8-olato-κ(2)N(1),O}tricarbonyl(pyridine-κN)rhenium(I), [Re(C28H23N6O)(CO)3], (II), are facially surrounded by three carbonyl ligands, a pyridine ligand and either a 5-[2-(2,4,6-trimethylphenyl)diazen-1-yl]quinolin-8-olate [in (I)] or a 5,7-bis[2-(2-methylphenyl)diazen-1-yl]quinolin-8-olate [in (II)] ligand, in a slightly distorted octahedral environment. The crystal structure of (I) is stabilized by two intermolecular C-H···O interactions and that of (II) is stabilized by three intermolecular C-H···O hydrogen-bonding interactions. Read More

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December 2013

Arrangement of Rh3+ ions in fac-triamminetrichloridorhodium from powder data and in fac-triamminetrinitratorhodium crystals twinned by merohedry.

Acta Crystallogr C 2013 Dec 15;69(Pt 12):1462-6. Epub 2013 Nov 15.

Kirensky Institute of Physics SB RAS, Akademgorodok, Krasnoyarsk 660036, Russia.

The rhodium complexes [RhCl3(NH3)3], (I), and [Rh(NO3)3(NH3)3], (II), are built from octahedral RhX3(NH3)3 units; in (I) they are isolated units, while in (II) the units are stacked in columns with partially filled sites for the Rh atoms. The octahedra of monoclinic crystals of (I) are linked by N-H···Cl hydrogen bonds and the Rh(3+) ions are located on the mirror planes. In the trigonal crystals of (II), the discontinuous `columns' along the threefold axis are linked by N-H···O hydrogen bonds. Read More

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December 2013

On the possibility for Rb- and Eu-cation ordering in type-I clathrates: synthesis and homogeneity range of the novel compounds Rb(8-x)Eu(x)(In,Ge)46 (0.6 ≤ x ≤ 1.8).

Acta Crystallogr C 2013 Dec 13;69(Pt 12):1457-61. Epub 2013 Nov 13.

Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA.

Studies in the Rb-Eu-In-Ge system confirm the existence of the phase Rb(8-x)Eu(x)(In,Ge)46 (0.6 ≤ x ≤ 1.8), crystallizing with the cubic clathrate type-I structure. Read More

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December 2013

Solid-state photochemistry of molecular photo-switchable species: the role of photocrystallographic techniques.

Acta Crystallogr C 2013 Dec 30;69(Pt 12):1448-56. Epub 2013 Nov 30.

Department of Chemistry, University of Bath, Claverton Down, Bath, Avon BA2 7AY, England.

Over the last 30 years, the single-crystal photocrystallographic technique has been developed to determine the three-dimensional crystal and molecular structures of metastable species which have been generated in the crystal photochemically. Transition-metal complexes that have been investigated using this methodology include complexes that contain nitrosyl, dinitrogen, sulfur dioxide and nitrite ligands, all of which form new linkage isomers in the solid state when photoactivated by light of the appropriate wavelength. Both steric and electronic factors determine the level of the conversion from the ground-state structure to the metastable isomeric structure, and both the `reaction cavity' size and the nature of the intermolecular interactions are shown to be among the key factors that influence the percentage conversion. Read More

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December 2013

Structure, magnetism and colour in simple bis(phosphine)nickel(II) dihalide complexes: an experimental and theoretical investigation.

Acta Crystallogr C 2013 Dec 30;69(Pt 12):1437-47. Epub 2013 Nov 30.

School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Gardens Point QLD 4000, Australia.

The complex [1,2-bis(di-tert-butylphosphanyl)ethane-κ(2)P,P']diiodidonickel(II), [NiI2(C18H40P2] or (dtbpe-κ(2)P)NiI2, [dtbpe is 1,2-bis(di-tert-butylphosphanyl)ethane], is bright blue-green in the solid state and in solution, but, contrary to the structure predicted for a blue or green nickel(II) bis(phosphine) complex, it is found to be close to square planar in the solid state. The solution structure is deduced to be similar, because the optical spectra measured in solution and in the solid state contain similar absorptions. In solution at room temperature, no (31)P{(1)H} NMR resonance is observed, but the very small solid-state magnetic moment at temperatures down to 4 K indicates that the weak paramagnetism of this nickel(II) complex can be ascribed to temperature independent paramagnetism, and that the complex has no unpaired electrons. Read More

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December 2013

NMR diffusion: an update.

Authors:
Paul S Pregosin

Acta Crystallogr C 2013 Dec 21;69(Pt 12):1433-6. Epub 2013 Nov 21.

Laboratory of Inorganic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, Wolfgang-Pauli-Straße 10, Zürich, CH-8093, Switzerland.

NMR diffusion methods continue to attract increasing attention from practising chemists. This short article summarizes some of the more recent developments and highlights the areas in which these methods are finding application, specifically: estimating molecular volumes; investigating the degree of aggregation (especially in salts); studying host-guest interactions; recognizing hydrogen bonds; and directly proving the presence and extent of ion pairing. Read More

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December 2013

Powder diffraction: what's in a name?

Acta Crystallogr C 2013 Dec 8;69(Pt 12):1431-2. Epub 2013 Nov 8.

APS, Argonne National Laboratory, 9700 S. Cass Ave., Lemont, IL 60439-4814, USA.

The development of powder diffraction is briefly described; the extent of this development from studies of metals to protein crystal structures shows that powder diffraction is at the cutting edge of crystallography. A new name `polycrystallography' is proposed for these endeavours. Read More

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December 2013

Bis(1,1,1,5,5,5-hexafluoropentane-2,4-dionato)tetrakis(μ4-1,1,1,5,5,5-hexafluoropentane-2,2,4,4-tetraolato)copper(II)octatin(II): a prospective precursor for Cu-doped SnO2 films.

Acta Crystallogr C 2013 Dec 8;69(Pt 12):1427-30. Epub 2013 Nov 8.

Department of Chemistry, University at Albany, Albany, NY 12222, USA.

The crystal structure of a tin-rich heterometallic supramolecular product, [CuSn8(C5HF6O2)2(C5H2F6O4)4] or [Sn4(hfpt)2-Cu(hfac)2-Sn4(hfpt)2], (I), is reported (hfpt is the tetraanion of 1,1,1,5,5,5-hexafluoropentane-2,2,4,4-tetraol and hfac is the anion of 1,1,1,5,5,5-hexafluoropentane-2,4-dione). Reaction between tin(II) tetraolate, [Sn4(hfpt)2], and copper(II) β-diketonate, [Cu(hfac)2], was utilized for the preparation of (I). The asymmetric unit consists of the whole [Sn4(hfpt)2] unit and half of a [Cu(hfac)2] unit, with the Cu atom lying on an inversion center. Read More

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December 2013

Ru(II)-hydride-trop complexes: X-ray single-crystal determination and quantum-chemical calculations.

Acta Crystallogr C 2013 Dec 8;69(Pt 12):1421-6. Epub 2013 Nov 8.

Department of Chemistry and Applied Biosciences, ETH Zürich, Wolfgang Pauli Strasse 10, CH-8093 Zurich, Switzerland.

As part of our search for catalytically active Ru(II)-hydride complexes, we have synthesized and crystallographically characterized three different ruthenium species, namely dihydrido[(SR)-(10,11-η)-N-(pyridin-2-ylmethyl-κN)-5H-dibenzo[a,d]cyclohepten-5-amine](triphenylphosphane-κP)ruthenium(II) tetrahydrofuran monosolvate, [RuH2(C21H18N2)(C18H15P)]·C4H8O or (SR)-[Ru(II)(H)2{N-(pyridin-2-ylmethyl)tropNH}(PPh3)]·THF, (1), chlorido{(1SR,2RS)-N,N'-bis[(10,11-η)-5H-dibenzo[a,d]cyclohepten-5-amine]ethane-1,2-diamine-κ(2)N,N'}hydridoruthenium(II) dimethoxyethane hemisolvate, [RuClH(C32H28N2)]·0.5C4H10O2 or (1SR,2RS)-[Ru(II)(H)(Cl){tropNH(CH2)2HNtrop}]·DME, (2), and chlorido{(1SR,2RS)-N,N'-bis[(10,11-η)-5H-dibenzo[a,d]cyclohepten-5-amine]propane-1,3-diamine-κ(2)N,N'}hydridoruthenium(II), [RuClH(C33H30N2)] or (1SR,2RS)-[Ru(II)(H)(Cl){tropNH(CH2)3HNtrop}], (3), where trop is 5H-dibenzo[a,d]cycloheptene. In all three complexes, the Ru(II) center resides in an octahedral coordination environment. Read More

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December 2013