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Khrustalev V.n. - One of the best experts on this subject based on the ideXlab platform.
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Crystal structures and supramolecular features of 9,9-dimethyl-3,7-diazabicyclo[3.3.1]nonane-2,4,6,8-Tetraone, 3,7-diazaspiro[bicyclo[3.3.1]nonane-9,1′-cyclopentane]-2,4,6,8-Tetraone and 9-methyl-9-phenyl-3,7-diazabicyclo[3.3.1]nonane-2,4,6,8-Tetraon
'International Union of Crystallography (IUCr)', 2020Co-Authors: Vatsadze S.z., Vasilev E.v., Venskovsky N.u., Khrustalev V.n.Abstract:Compounds (I), C9H10N2O4, (II), C1 1H12N2O4, and (III), C1 4H12N2O4-C3H7NO represent 9,9-disubstituted-3,7-diazabicyclo[3.3.1]nonane-2,4,6,8-Tetraone derivatives with very similar molecular geometries for the bicyclic framework: The dihedral angle between the planes of the imide groups is 74.87 (6), 73.86 (3) and 74.83 (6)° in (I)-(III), respectively. The dimethyl derivative (I) is positioned on a crystallographic twofold axis and its overall geometry deviates only slightly from idealized C2v symmetry. The spiro-cyclopentane derivative (II) and the phenyl/ methyl analog (III) retain only internal Cs symmetry, which in the case of (II) coincides with crystallographic mirror symmetry. The cyclopentane moiety in (II) adopts an envelope conformation, with the spiro C atom deviating from the mean plane of the rest of the ring by 0.548 (2) A ° . In compound (III), an N-H·O hydrogen bond is formed with the dimethylformamide Solvent Molecule. In the crystal, both (I) and (II) form similar zigzag hydrogen-bonded ribbons through double intermolecular N-H·O hydrogen bonds. However, whereas in (I) the ribbons are formed by two trans-Arranged O C-N-H amide fragments, the amide fragments are cis-positioned in (II). The formation of ribbons in (III) is apparently disrupted by participation of one of its N-H groups in hydrogen bonding with the Solvent Molecule. As a result, the Molecules of (III) form zigzag chains rather than the ribbons through intermolecular N-H·O hydrogen bonds. The crystal of (I) was a pseudomerohedral twin. © Vatsadze et al. 2017
Victor N. Khrustalev - One of the best experts on this subject based on the ideXlab platform.
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Crystal structures and supramolecular features of 9,9-dimethyl-3,7-diazabicyclo[3.3.1]nonane-2,4,6,8-tetraone, 3,7-diazaspiro[bicyclo[3.3.1]nonane-9,1′-cyclopentane]-2,4,6,8-tetraone and 9-methyl-9-phenyl-3,7-diazabicyclo[3.3.1]nonane-2,4,6,8-tetraon
International Union of Crystallography, 2017Co-Authors: Sergey Z. Vatsadze, Marina A. Manaenkova, Evgeny V. Vasilev, Nikolai U. Venskovsky, Victor N. KhrustalevAbstract:Compounds (I), C9H10N2O4, (II), C11H12N2O4, and (III), C14H12N2O4·C3H7NO represent 9,9-disubstituted-3,7-diazabicyclo[3.3.1]nonane-2,4,6,8-tetraone derivatives with very similar molecular geometries for the bicyclic framework: the dihedral angle between the planes of the imide groups is 74.87 (6), 73.86 (3) and 74.83 (6)° in (I)–(III), respectively. The dimethyl derivative (I) is positioned on a crystallographic twofold axis and its overall geometry deviates only slightly from idealized C2v symmetry. The spiro-cyclopentane derivative (II) and the phenyl/methyl analog (III) retain only internal Cs symmetry, which in the case of (II) coincides with crystallographic mirror symmetry. The cyclopentane moiety in (II) adopts an envelope conformation, with the spiro C atom deviating from the mean plane of the rest of the ring by 0.548 (2) Å. In compound (III), an N—H...O hydrogen bond is formed with the dimethylformamide Solvent Molecule. In the crystal, both (I) and (II) form similar zigzag hydrogen-bonded ribbons through double intermolecular N—H...O hydrogen bonds. However, whereas in (I) the ribbons are formed by two trans-arranged O=C—N—H amide fragments, the amide fragments are cis-positioned in (II). The formation of ribbons in (III) is apparently disrupted by participation of one of its N—H groups in hydrogen bonding with the Solvent Molecule. As a result, the Molecules of (III) form zigzag chains rather than the ribbons through intermolecular N—H...O hydrogen bonds. The crystal of (I) was a pseudo-merohedral twin
Hakan Demiral - One of the best experts on this subject based on the ideXlab platform.
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effect of Solvent Molecule in pore for flexible porous coordination polymer upon gas adsorption and iodine encapsulation
Inorganic Chemistry, 2015Co-Authors: Mursel Arici, Okan Zafer Yesilel, Murat Tas, Hakan DemiralAbstract:Four new Zn(II)-coordination polymers, namely, [Zn2(μ6-ao2btc)(μ-obix)2]n (1), [Zn2(μ4-ao2btc)(μ-obix)2]n (2), [Zn2(μ4-ao2btc)(μ-mbix)2]n (3), and {[Zn2(μ4-ao2btc)(μ-pbix)2]·2DMF·8H2O}n (4), where ao2btc = dioxygenated form of 3,3′,5,5′-azobenzenetetracarboxylate and obix, mbix, and pbix = 1,2-, 1,3-, and 1,4-bis(imidazol-1-ylmethyl)benzene, have been synthesized with azobenzenetetracarboxylic acid and isomeric bis(imidazole) ligands and characterized by elemental analyses, IR spectra, single-crystal X-ray diffraction, powder X-ray diffraction, and thermal analyses. X-ray results showed that 1, 2, and 4 had two-dimensional structures with 3,4L13 topology, while 3 was a three-dimensional coordination polymer with bbf topology. For 4, two types of activation strategies, Solvent exchange + heating (which produced 4a) and direct heating (which produced 4b), were used to investigate the effect of a guest Molecule in a flexible framework. Gas adsorption and iodine encapsulation properties of activated complexes...
Patrick Nuernberger - One of the best experts on this subject based on the ideXlab platform.
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competitive Solvent Molecule interactions govern primary processes of diphenylcarbene in Solvent mixtures
Nature Communications, 2016Co-Authors: Johannes Knorr, Pandian Sokkar, Sebastian Schott, Paolo Costa, Walter Thiel, Wolfram Sander, Elsa Sanchezgarcia, Patrick NuernbergerAbstract:Photochemical reactions in solution often proceed via competing reaction pathways comprising intermediates that capture a Solvent Molecule. A disclosure of the underlying reaction mechanisms is challenging due to the rapid nature of these processes and the intricate identification of how many Solvent Molecules are involved. Here combining broadband femtosecond transient absorption and quantum mechanics/molecular mechanics simulations, we show for one of the most reactive species, diphenylcarbene, that the decision-maker is not the nearest Solvent Molecule but its neighbour. The hydrogen bonding dynamics determine which reaction channels are accessible in binary Solvent mixtures at room temperature. In-depth analysis of the amount of nascent intermediates corroborates the importance of a hydrogen-bonded complex with a protic Solvent Molecule, in striking analogy to complexes found at cryogenic temperatures. Our results show that adjacent Solvent Molecules take the role of key abettors rather than bystanders for the fate of the reactive intermediate. Photochemistry in solution often involves coexisting reaction channels that may comprise intermediates capturing a Solvent Molecule. Here, the authors show for one of the most reactive species, diphenylcarbene, that the decision-maker is not the nearest Solvent Molecule but its neighbour.
George Christou - One of the best experts on this subject based on the ideXlab platform.
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single Molecule magnets control by a single Solvent Molecule of jahn teller isomerism in mn12o12 o2cch2but 16 h2o 4
Chemical Communications, 2003Co-Authors: Monica Soler, Wolfgang Wernsdorfer, Ziming Sun, John C Huffman, David N Hendrickson, George ChristouAbstract:Faster- and slower-relaxing versions of the title Mn12 compound have been obtained in pure forms that crystallize in the same space group and differ only in the identity of one lattice Solvent Molecule; Solvent loss causes isomerization from the faster- to the slower-relaxing form.
