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ABSTRACT: AbstractSynthesis and characterization of single crystals of a new organic Schiff-base derivative, N,N′-bis(2,3-dimethoxybenzylidene)-1,2-diaminoethane is reported. Good quality single crystals with size 10mm×1mm×1mm were
grown by slow evaporation technique from a methanol solution at room temperature. The grown crystals have been characterized
by elemental analyses and functional groups were identified using FT-IR and 1H-NMR spectroscopy. Crystal structure of the title compound has been determined by single crystal X-ray diffraction. The title
compound has a monoclinic symmetry, space group P21/c, lattice parameters are a=4.4159(3)Å, b=14.2333(9)Å, c=15.0601(10)Å, β=97.755(5)°, Z=2, V=937.91(11)Å3.
Graphical Abstract
KeywordsCharacterization–Single crystals–Schiff-base–X-ray diffraction
Journal of Chemical Crystallography 05/2012; 41(12):1955-1960. · 0.57 Impact Factor
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ABSTRACT: The title Schiff-base compound, 6-[(5-Bromopyridin-2-yl)iminomethyl]phenol (1), has been synthesized and characterized by elemental analyses, FT-IR, UV–Vis and 1H-NMR spectroscopy, and X-ray single crystal diffraction. In the gas phase four isomers were found for title compound. Density
functional (DFT) calculations have been carried out and it was found that the A isomer is the most stable one. The protonated imine N atom is involved in intra- and inter-molecular hydrogen bonds with
the phenoxide group and H aromatic atoms, respectively. The title compound displays a trans configuration about the C=N double bond.
Structural Chemistry 05/2012; 21(1):153-157. · 1.85 Impact Factor
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ABSTRACT: AbstractUsing 1,4,8,11-tetraazacyclotetradecane (cyclam) as a template, two new layered zincophosphites, Zn(HPO3)2·0.5(C10H28N4) (1) and Zn2(HPO3)3·0.5(C10H28N4) (2), were synthesized and characterized by single crystal X-ray diffraction. The two new compounds crystallize in the triclinic
system with the space group P−1 and the cell parameters: a=8.3130Å, b=8.7289Å, c=9.0055Å, α=106.90(1), β=95.56(1), γ=105.30(1), V=592.31Å3, Z=2 for 1 and a=9.0406Å, b=9.4234Å, c=9.4519Å, α=91.19(1), β=100.73(1), γ=106.85(1), V=754.82Å3, Z=2 for 2. Both structures are described in terms of phosphometallic slabs hosting the cyclam cation.
Graphical AbstractBoth new compounds Zn(HPO3)2·0.5(C10H28N4) and Zn2(HPO3)3·0.5(C10H28N4) consist in zincophosphite slabs hosting the tetraprotonated organic cyclam (C10H28N4)4+.
KeywordsHybrid phosphates–Cyclam–Wet chemistry–Single crystal structure–IR spectroscopy
Journal of Chemical Crystallography 04/2012; 41(2):223-229. · 0.57 Impact Factor
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ABSTRACT: The asymmetric unit of the title compound, C(12)H(17)NO(3), contains two mol-ecules with different conformations. It is a polymorph of the monoclinic form [El Antri et al. (2004 ▶). Mol-ecules, 9, 650-657]; the samples were crystallized at different temperatures from the same solvent. In both structures, mol-ecules are linked by O-H⋯N hydrogen bonds, forming chains. The conformations of the chains and their packing differ markedly in the two polymorphs.
Acta Crystallographica Section E Structure Reports Online 07/2011; 67(Pt 7):o1734-5. · 0.35 Impact Factor
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ABSTRACT: Methods for the preparation of anion-free bambus[6]uril (BU6) are presented. They are based on the oxidation of iodide anion, which is bound inside the macrocycle, utilizing dark oxidation by hydrogen peroxide or photooxidation in the presence of titanium dioxide. Anion-free BU6 was found to be insoluble in any of the investigated solvents; however, it dissolves in methanol/chloroform (1:1) or acetonitrile/water (1:1) mixtures in the presence of the tetrabutylammonium salt of a suitable anion. The association constants with halide ions, BF(4)(-), NO(3)(-), and CN(-), were measured by (1)H NMR spectroscopy. The highest association constant (8.9×10(5) M(-1)) was found for the 1:1 complex of BU6 with I(-) in acetonitrile/water mixture. A number of crystal structures of BU6 complexes with various anions were obtained. The influence of the anion size on the macrocycle diameter is discussed together with an unusual arrangement of the macrocycles into separate layers.
Chemistry 05/2011; 17(20):5605-12. · 5.93 Impact Factor
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ABSTRACT: The title Schiff base compound, C(22)H(28)N(2)O(4), was synthesized by the reaction of 3,4-dimethoxy-benzaldehyde and 1,4-diamino-butane in methanol. The mol-ecule is located on a center of inversion with one half-mol-ecule in the asymmetric unit. Both C=N double bonds are in a trans configuration. Inter-molecular C-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional network.
Acta Crystallographica Section E Structure Reports Online 01/2009; 65(Pt 8):o1773. · 0.35 Impact Factor
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ABSTRACT: The title compound, C(32)H(28)N(2)O, is a flexible Schiff base displaying a trans configuration across the C=N double bond. It was prepared in high yield by condensation of α-methyl-cinnamaldehyde and bis-(4-amino-phen-yl) ether in methanol at room temperature. The sample, with pseudo-ortho-rhom-bic cell parameters, exhibited merohedral twinning by rotation 180° around a*, with a refined twin domain fraction of 0.722 (1). The elongated shape of the elementary cell corresponds to the shape and direction of the mol-ecules. The dihedral angle between the O-linked aromatic rings is 57.86 (8)°.
Acta Crystallographica Section E Structure Reports Online 01/2009; 65(Pt 3):o538. · 0.35 Impact Factor
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ABSTRACT: The crystal structures of three isotypic orthorhombic dihydrogendiphosphates, namely dipotassium copper(II)/nickel(II)/zinc(II) bis(dihydrogendiphosphate) dihydrate, K2M(H2P2O7)2.2H2O (M = Cu, Ni and Zn), have been refined from single-crystal data. The M2+ and K+ cations are located at sites of m symmetry, and the P atoms occupy general positions. These compounds also exist in triclinic forms with very similar structural features. The structures of both forms are compared, as well as the geometry of the MO6 octahedron, which is considerably elongated towards the water molecules for M = Ni and Cu. Such elongation has not been observed among the other representatives of the family. A Raman study of the whole series K2M(H2P2O7)2.2H2O (M = Mn, Co, Ni, Cu, Zn and Mg) is reported.
Acta Crystallographica Section C Crystal Structure Communications 01/2006; 61(Pt 12):m120-4. · 0.52 Impact Factor