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ABSTRACT Nickel and cobalt heterocubanes have been synthesised from dinuclear complexes. The use of 8-hydroxyquinaldine leads to a rhombohedral distortion in two faces of the cubes. Both cubes were studied by paramagnetic NMR, which shows... more
ABSTRACT Nickel and cobalt heterocubanes have been synthesised from dinuclear complexes. The use of 8-hydroxyquinaldine leads to a rhombohedral distortion in two faces of the cubes. Both cubes were studied by paramagnetic NMR, which shows that they are stable in solution. Magnetic measurements show that the coupling within both molecules is overall antiferromagnetic. The magnetic data for the nickel cube has been modelled, and shows that the coupling consists of two ferromagnetically coupled pairs which are antiferromagnetically coupled to give a diamagnetic ground state.
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ANA MARIA ATRIA et ai 1067 these two mean planes is 64J°. The structure is stfl-bilized by short nonbonding contacts [Br(l) ■ -HO) C{1) ■ 2.985 and Br(2)-♦ H(7U)C(7) - 2.915 ÃJ and mtennotectibr bonds [Br(2) * H(l)C(l) - 2.914, Br(2).... more
ANA MARIA ATRIA et ai 1067 these two mean planes is 64J°. The structure is stfl-bilized by short nonbonding contacts [Br(l) ■ -HO) C{1) ■ 2.985 and Br(2)-♦ H(7U)C(7) - 2.915 ÃJ and mtennotectibr bonds [Br(2) * H(l)C(l) - 2.914, Br(2). - H(3) C(3) - 2.964 andBr(l). ...
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An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely... more
An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely... more
An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Abstract The title chalcone, 1,3-di(thiophene-3-yl)prop-2-en-1-one (C11H8OS2) is an essentially planar molecular with its terminal thiophene rings subtending an angle of 8.9°. The crystal structure consists in the π··π stacking of... more
Abstract The title chalcone, 1,3-di(thiophene-3-yl)prop-2-en-1-one (C11H8OS2) is an essentially planar molecular with its terminal thiophene rings subtending an angle of 8.9°. The crystal structure consists in the π··π stacking of molecules defining columns along [010], further linked along c by non conventional C H⋯O bonds, thus determining broad planar arrays parallel to (100). In addition, there are weak S⋯S contacts connecting these weakly interacting 2D substructures. The experimental results obtained from single crystal X-ray diffraction data and the theoretical geometry calculated by molecular mechanics are in good agreement. Electrochemical records reveal an anodic profile with an unsymmetrical irreversible peak at 1.77 V and a shoulder at 1.62 V vs SCE, a behavior interpretable as due to the oxidation of reactive sites present in the molecule. On the other hand, the electrochemical reduction shows a narrow peak at −1.58 V vs SCE, a fact attributable to the carbonyl group. Finally, the values for the energy involved in the departure/arrival of electrons from border orbitals, as calculated using DFT, is compared with experimental data from cyclic voltammetry.
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Pyrolysis of the organometallic polymer: {{[N=P(R1)]0.8[N=P(OC6H4CH2CN[Ru])2]0.15[N=P((OC6H5)(OC6H4CH2CN[Ru]]0.05}{Cl}0.31} n , [Ru]=CpRu(PPh3)2, R1 = O2C12H8 (1) as well of the cyclic specie {N3P3 (OC6H5)5(OC6H4CH2CN[Ru])}{PF6} (2) under... more
Pyrolysis of the organometallic polymer: {{[N=P(R1)]0.8[N=P(OC6H4CH2CN[Ru])2]0.15[N=P((OC6H5)(OC6H4CH2CN[Ru]]0.05}{Cl}0.31} n , [Ru]=CpRu(PPh3)2, R1 = O2C12H8 (1) as well of the cyclic specie {N3P3 (OC6H5)5(OC6H4CH2CN[Ru])}{PF6} (2) under a flow of air at 800�C affords nanostructured RuO2. Nanoparticles near to 10 nm were observed. The differences in the use of cyclic or polymeric phosphazenes, as solid state template, influence strongly the morphology and slightly the composition of the pyrolytic product. Temperature variable (SQUID) measurements in the range of 5–300 K of the material obtained from the polymer, indicate an antiferromagnetic interaction between the Ru atoms, although lower than that found for the crystalline ruthenium oxide, probably due to some amorphous product present in the pyrolytic material. The possible formation mechanism is discussed and the differences in using the cyclic or the polymeric compound as precursor is analyzed in terms of the relative content of Ru to P, N. A general formation method of nanostructured metal oxides is proposed.
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An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely... more
An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
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An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely... more
An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
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An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely... more
An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
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A new MnIII complex exhibits a gradual spin crossover phenomenon with single crystal thermochromism. A comparative structural study was conducted using octahedral deviation parameters.
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The title mononuclear Cocomplex, [Co(CHN)(CHO)(HO)]·2HO, has been synthesized and its crystal structure determined by X-ray diffraction. The complex crystallizes in the triclinic space group P-1, with one formula unit per cell (Z = 1 and... more
The title mononuclear Cocomplex, [Co(CHN)(CHO)(HO)]·2HO, has been synthesized and its crystal structure determined by X-ray diffraction. The complex crystallizes in the triclinic space group P-1, with one formula unit per cell (Z = 1 and Z' = 1/2). It consists of a mononuclear unit with the Coion on an inversion centre coordinated by two 2,6-diamino-7H-purin-1-ium cations, two 4,4'-oxydibenzoate anions (in a nonbridging κO-monodentate coordination mode, which is less common for the anion in its Cocomplexes) and two water molecules, defining an octahedral environment around the metal atom. There is a rich assortment of nonbonding interactions, among which a strong N-H...Obridge, with a short N...O distance of 2.5272 (18) Å, stands out, with the H atom ostensibly displaced away from its expected position at the donor side, towards the acceptor. The complex molecules assemble into a three-dimensional hydrogen-bonded network. A variable-temperature magnetic study between 2 and 3...
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In the title monomer, [Cu(NO(3))(2)(C(18)H(12)N(2))], the six-coordinated Cu(II) atom lies on a twofold axis which bisects one of the ligands (a chelating biquinoline) and duplicates the remaining ligand, a chelating nitrate. The latter... more
In the title monomer, [Cu(NO(3))(2)(C(18)H(12)N(2))], the six-coordinated Cu(II) atom lies on a twofold axis which bisects one of the ligands (a chelating biquinoline) and duplicates the remaining ligand, a chelating nitrate. The latter binds in a very asymmetric way, consistent with a Jahn-Teller distortion in the coordination polyhedron which, due to the triple chelation, is extremely distorted and difficult to describe in terms of any regular model.
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ABSTRACT The title compounds, poly[bis(2,2′-bipyridine)bis(μ3-hydrogen phosphato)nitratodi-μ2-oxo-dicopper(II)vanadium dihydrate], [Cu2(VO2)(HPO4)2(NO3)(C10H8N2)2]·2H2O, (I), and poly[bis(2,2′-bipyridine)bis(μ3-hydrogen... more
ABSTRACT The title compounds, poly[bis(2,2′-bipyridine)bis(μ3-hydrogen phosphato)nitratodi-μ2-oxo-dicopper(II)vanadium dihydrate], [Cu2(VO2)(HPO4)2(NO3)(C10H8N2)2]·2H2O, (I), and poly[bis(2,2′-bipyridine)bis(μ3-hydrogen phosphato)nitratodi-μ2-oxo-dicopper(II)vanadium phosphoric acid solvate], [Cu2(VO2)(HPO4)2(NO3)(C10H8N2)2]·H3PO4, (II), were obtained by similar hydrothermal methods but under different crystallization conditions. The trinuclear entity which serves as the basic unit in both structures presents two independent CuII ions immersed in similar square-pyramidal N2O3 environments plus an octahedral VO6 core and is organized into a one-dimensional polymer, which is essentially identical in the two structures. The compounds are stabilized by different solvates, viz. two crystallization water molecules in (I) and a phosphoric acid molecule in (II), which provide the main structural differences through the diversity of interchain interactions in which they serve as bridges.
In the title monomer, [Cu(NO3)2(C24H16N2)2], the copper(II) cation is eight-coordinate within an octahedral-like polyhedron. The coordination polyhedron is formed by two chelating diphenylphenanthroline groups that define the highly... more
In the title monomer, [Cu(NO3)2(C24H16N2)2], the copper(II) cation is eight-coordinate within an octahedral-like polyhedron. The coordination polyhedron is formed by two chelating diphenylphenanthroline groups that define the highly distorted CuN4 equatorial plane and two weakly bound bidentate (chelating) nitrate groups in the apical or axial positions. The complex crystallizes in the monoclinic space group C2/c; a twofold axis passes through the copper(II) cation and bisects the two nitrate ligands. This gives the molecule C2 point-group symmetry, rendering only half of the molecule independent.
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ABSTRACT The title complex, [CuBr2(C12H11N3)], is a monomer and the environment around the Cu2+ ion is that of a square pyramid, with one Br- ion occupying the apical site and the other Br- ion at a basal position.
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Over the last decade the design and synthesis of metal-organic compounds with fascinating structural properties and potential applications as functional materials has been a major challenge in various fields of research.1Strategies for... more
Over the last decade the design and synthesis of metal-organic compounds with fascinating structural properties and potential applications as functional materials has been a major challenge in various fields of research.1Strategies for preparing these compounds are based on the careful selection of the constituent building blocks. 4'-(substituted)-4,2':6',4''-terpyridine ligands are considered versatile building blocks for the assembly of coordination polymers and networks with useful solid-state properties, such as magnetism, luminescence, redox activity, etc.2The divergent arrangements of N-donor atoms and the attachment of aryl substituents into the 4'-position of…
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Heterometallic compounds comprising copper(II) and rare-earth cations with carboxylate groups of the 2,2′-oxydiacetato as the connecting ligands, have been investigated. Five isostructural polymers [{Cu3Ln2(oda)6(H2O)6}·12H2O]n (Ln = Y... more
Heterometallic compounds comprising copper(II) and rare-earth cations with carboxylate groups of the 2,2′-oxydiacetato as the connecting ligands, have been investigated. Five isostructural polymers [{Cu3Ln2(oda)6(H2O)6}·12H2O]n (Ln = Y (1), Gd (2), Eu (3), Nd (4) and Pr (5)) have been obtained and their structures determined by X-ray diffraction methods. The Ln(III) cations in 1 to 5 are coordinated by six carboxy and three ether oxygen atoms in the tricapped trigonal prism arrangement and the Cu(II) cations are bonded to four carboxy oxygens and two apical aqua ligands in a distorted octahedral geometry. The magnetic behaviors of these complexes show very weak antiferromagnetic interaction in the solid.
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ABSTRACT The title complex, [CuBr2(C12H11N3)], is a monomer and the environment around the Cu2+ ion is that of a square pyramid, with one Br- ion occupying the apical site and the other Br- ion at a basal position.
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In the title monomer, [Cu(NO(3))(2)(C(18)H(12)N(2))], the six-coordinated Cu(II) atom lies on a twofold axis which bisects one of the ligands (a chelating biquinoline) and duplicates the remaining ligand, a chelating nitrate. The latter... more
In the title monomer, [Cu(NO(3))(2)(C(18)H(12)N(2))], the six-coordinated Cu(II) atom lies on a twofold axis which bisects one of the ligands (a chelating biquinoline) and duplicates the remaining ligand, a chelating nitrate. The latter binds in a very asymmetric way, consistent with a Jahn-Teller distortion in the coordination polyhedron which, due to the triple chelation, is extremely distorted and difficult to describe in terms of any regular model.
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Two polymorphic forms of a mixed zinc/copper biquinoline dihydrogenphosphate are presented, showing almost identical monomeric units, viz.... more
Two polymorphic forms of a mixed zinc/copper biquinoline dihydrogenphosphate are presented, showing almost identical monomeric units, viz. (2,2'-biquinoline-kappa(2)N,N')bis(dihydrogenphosphato-kappaO)copper(II)/zinc(II), formulated as [Zn(x)Cu(1-x)(H(2)PO(4))(2)(C(18)H(12)N(2))], with x = 0.88 (1) and 0.90 (2). The cation is tetrahedrally coordinated to a chelating biquinoline system and two diprotonated phosphate anions. The structures differ mainly in their intermolecular hydrogen-bonding interactions, leading to different packing schemes. No significant evidence of stress due to the Zn/Cu solid solution formation was detected.
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In the title monomer, [Cu(NO3)2(C24H16N2)2], the copper(II) cation is eight-coordinate within an octahedral-like polyhedron. The coordination polyhedron is formed by two chelating diphenylphenanthroline groups that define the highly... more
In the title monomer, [Cu(NO3)2(C24H16N2)2], the copper(II) cation is eight-coordinate within an octahedral-like polyhedron. The coordination polyhedron is formed by two chelating diphenylphenanthroline groups that define the highly distorted CuN4 equatorial plane and two weakly bound bidentate (chelating) nitrate groups in the apical or axial positions. The complex crystallizes in the monoclinic space group C2/c; a twofold axis passes through the copper(II) cation and bisects the two nitrate ligands. This gives the molecule C2 point-group symmetry, rendering only half of the molecule independent.
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ABSTRACT The title compounds, poly[bis(2,2′-bipyridine)bis(μ3-hydrogen phosphato)nitratodi-μ2-oxo-dicopper(II)vanadium dihydrate], [Cu2(VO2)(HPO4)2(NO3)(C10H8N2)2]·2H2O, (I), and poly[bis(2,2′-bipyridine)bis(μ3-hydrogen... more
ABSTRACT The title compounds, poly[bis(2,2′-bipyridine)bis(μ3-hydrogen phosphato)nitratodi-μ2-oxo-dicopper(II)vanadium dihydrate], [Cu2(VO2)(HPO4)2(NO3)(C10H8N2)2]·2H2O, (I), and poly[bis(2,2′-bipyridine)bis(μ3-hydrogen phosphato)nitratodi-μ2-oxo-dicopper(II)vanadium phosphoric acid solvate], [Cu2(VO2)(HPO4)2(NO3)(C10H8N2)2]·H3PO4, (II), were obtained by similar hydrothermal methods but under different crystallization conditions. The trinuclear entity which serves as the basic unit in both structures presents two independent CuII ions immersed in similar square-pyramidal N2O3 environments plus an octahedral VO6 core and is organized into a one-dimensional polymer, which is essentially identical in the two structures. The compounds are stabilized by different solvates, viz. two crystallization water molecules in (I) and a phosphoric acid molecule in (II), which provide the main structural differences through the diversity of interchain interactions in which they serve as bridges.
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The first two crystal structures of enamines derived from 1-n-alkyl-3-methyl-5-pyrazolones, namely 1-(n-hexyl)-3-methyl-4-[1-(phenylamino)propylidene]-2-pyrazolin-5-one, C19H27N3O, (I), and... more
The first two crystal structures of enamines derived from 1-n-alkyl-3-methyl-5-pyrazolones, namely 1-(n-hexyl)-3-methyl-4-[1-(phenylamino)propylidene]-2-pyrazolin-5-one, C19H27N3O, (I), and N,N'-bis[1-[1-(n-hexyl)-3-methyl-5-oxo-2-pyrazolin-4-ylidene]ethyl]hexane-1,6-diamine, C30H52N6O2, (II), are reported. The molecule of (II) lies about an inversion centre. Both (I) and (II) are stabilized by intramolecular N-H...O hydrogen bonding. This confirms previous results based on spectroscopic evidence alone.
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... The optimal conditions values were determined over the response surface by the SIMPLEX method.16 All the calculations were carried out using the Modde 7.0 software. Discussion. From the results of the multivariate analyses a... more
... The optimal conditions values were determined over the response surface by the SIMPLEX method.16 All the calculations were carried out using the Modde 7.0 software. Discussion. From the results of the multivariate analyses a polynomial response to crystal amount was ...
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... Fredy R. Péreza, Julio Belmar*b, Yanko Morenob, Ricardo Baggioc and Octavio Peñad. a Facultad de Ciencias de la ... 1, (a) RA Sheldon and JK Kochi, Metal-Catalyzed Oxidation of Organic Compounds, Academic Press, New York, 1981 ; (b)... more
... Fredy R. Péreza, Julio Belmar*b, Yanko Morenob, Ricardo Baggioc and Octavio Peñad. a Facultad de Ciencias de la ... 1, (a) RA Sheldon and JK Kochi, Metal-Catalyzed Oxidation of Organic Compounds, Academic Press, New York, 1981 ; (b) EN Jacobsen, in Comprehensive ...