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1.
Marijana ?aković Zora Popović 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(11):m507-m509
In the title compound, [Ni(N3)2(C6H6N2O)2], the NiII atom lies on an inversion centre. The distorted octahedral nickel(II) coordination environment contains two planar trans-related N,O-chelating picolinamide ligands in one plane and two monodentate azide ligands perpendicular to this plane. Molecules are linked into a three-dimensional framework by N—H...N hydrogen bonds. 相似文献
2.
Boris‐Marko Kukovec Zora Popovi Gordana Pavlovi 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(9):m389-m391
In the title compound, [Cd(C7H6NO2)2]n, the CdII ion has a distorted octahedral geometry. The 6‐methylpyridine‐2‐carboxylate anions are perpendicular to one another and act as bidentate and bridging ligands. Two carboxylate O atoms bridge the CdII ions, forming centrosymmetric dinuclear units. These units are further connected via carboxylate O atoms into a one‐dimensional polymeric chain which extends in the [100] direction. 相似文献
3.
Dubravka Matković-Čalogović Zora Popović Branka Korpar-Čolig 《Journal of chemical crystallography》1995,25(8):453-458
[Hg(terpy)2](CF3SO3)2·0.5(CH3)2CO crystallizes in the triclinic
space group witha=14.631(6),b=15.258(4),c=18.785(7) Å, =69.66(2), =70.72(1), =88.55(1)°. The crystal structure consists of two independent [Hg(terpy)2]2+ cations, four trifluoromethanesulfonate anions and an acetone molecule in the asymmetric unit. Each mercury atom is coordinated by two tridentate terpyridine ligands forming an irregular six-coordination polyhedron. The Hg–N bond lengths range from 2.27(2) to 2.53(2) Å. 相似文献
4.
A squarate-based synthesis of 2-ferrocenylidene-4-cyclopentene-1,3-diones is described. When refluxed in dioxane at 100 °C, heated with silica gel as a solvent free grinded solid mixture at 125 °C or stirred with silica gel in ethyl acetate at room temperature, 4-ferrocenylethynyl-4-hydroxy-2-cyclobutenones, prepared from ethynylferrocene and 3-cyclobutene-1,2-diones, afforded 2-ferrocenylidene-4-cyclopentene-1,3-diones as the major or single product of the reaction. In some cases, ferrocenyl quinones also resulted from these reactions as the minor products. The major or exclusive formation of 2-ferrocenylidene-4-cyclopentene-1,3-diones is attributed to the radical-stabilizing ability of the ferrocenyl group. 相似文献
5.
Polacco G Stastna J Biondi D Antonelli F Vlachovicova Z Zanzotto L 《Journal of colloid and interface science》2004,280(2):366-373
Asphalt is known to be a colloidal suspension in which asphaltenes are covered by a stabilizing phase of polar resins and form complex micelles that are dispersed in the oily maltenic phase. In order to enhance its mechanical properties (e.g., in road paving), asphalts are often loaded with polymeric materials, thereby obtaining blends that can have different physical or chemical structures, depending on the composition of the added polymer. Asphalts modified by the addition of reactive ethylene terpolymers were prepared and their dielectric and rheological properties were measured both before and after a cure at high temperature. Even if it is not possible to determine the exact nature of the chemical interactions between asphalt and polymer, master curves obtained from dynamic data clearly show that during the cure the material tends to the behavior of a cross-linked network. 相似文献
6.
A novel synthesis of 1,2,4-oxadiazoles and isoxazoles is described by utilizing the reactions between amidoximes and α,β-alkynic aldehydes and/or ketones. Conjugate addition products, obtained from amidoximes and α,β-alkynic aldehydes and/or ketones, afford 1,2,4-oxadiazoles and isoxazoles when treated with bases and acids, respectively. 1,2,4-Oxadiazoles can also be synthesized directly from amidoximes and α,β-alkynic aldehydes in a one-pot manner under basic conditions. The reactions are general for a variety of starting compounds and tolerate the presence of aryl, heteroaryl and alkyl groups. 相似文献
7.
Electrophilic cyclizations of α,β-alkynic hydrazones by molecular iodine were investigated for the synthesis of 4-iodopyrazoles. α,β-Alkynic hydrazones were readily prepared by the reactions of hydrazines with propargyl aldehydes and ketones. When treated with molecular iodine in the presence of sodium bicarbonate, α,β-alkynic hydrazones underwent electrophilic cyclization to afford 4-iodopyrazoles in good to high yields. Iodocyclization was general for a wide range of α,β-alkynic hydrazones and tolerated the presence of aliphatic, aromatic, heteroaromatic, and ferrocenyl moieties with electron-withdrawing and electron-donating substituents. 相似文献
8.
Ma?a?Raji?? Linari? Zora?Popovi?Email author ?eljka?Soldin 《Journal of Thermal Analysis and Calorimetry》2007,88(2):489-493
This work presents preparation and thermal characterization of three
novel organomercurials: Hg2(CF3COCHCOCF3)2-μ2-(CF3COCCOCF3)μ2(CF3C(OH)2CH2C(OH)2CF3)
(I), Hg2(CF3COCHCOCF3)2-μ2-(CF3COCCOCF3)
(II) and Hg2(CH3COCHCOCF3)2-μ2-(CH3COCCOCF3)
(III) which means that they contain at least
one direct mercury-to-carbon bond among the carbonyl groups of β-diketone
molecules which are capable for chelating of metal ions. IR-spectra support
the conclusion that mercury is most probably bound to the γ-carbon of
fluorinated derivatives of acetylacetone and is not chelated through oxygen
in any of the isolated compounds.
The thermal decomposition of
mercurated hexafluoro- and trifluoroacetylacetone in nitrogen occurs in a
few steps. Each step was identified and studied by simultaneous DTA/TG analyzer.
On the basis of dynamic heating experiments by TG applying Flynn-Wall method
the activation energy for each of them was determined. 相似文献
9.
Günseli Turgut Metin Zora Mustafa Odabaolu Cem Cüneyt Ersanl Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(5):o321-o323
The crystal structure of the title compound, C2H10N2O2+·2Cl−, is built up from one 2‐hydroxyethylhydrazinium(2+) cation and two Cl− anions. The molecular structure is stabilized by O—H⋯Cl and N—H⋯Cl hydrogen bonds. The crystal structure is stabilized by one N—H⋯O and three N—H⋯Cl interactions, and the three‐dimensional network of hydrogen bonds stabilizes the crystal packing. All five hydrazinium H atoms are involved in hydrogen bonds to Cl− anions. The Cl⋯H contact distances range from 2.122 (15) to 2.809 (14) Å. 相似文献
10.