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991.
Jill E. Morris Philip J. Squattrito Kristin Kirschbaum A. Alan Pinkerton 《Journal of chemical crystallography》2003,33(4):307-321
Salts of 4-aminonaphthalene-1-sulfonate with divalent Mg, Mn, Co, and Ni cations have been crystallized and their structures determined by single crystal X-ray methods. The Mg and Mn salts are isostructural. Crystal data for hexa-aquamagnesium(II) 4-aminonaphthalene-1-sulfonate dihydrate, [Mg(H2O)6](H2NC10H6SO3)2 2H
2O: monoclinic, P21/c, Z = 2, a = 8.622(3), b = 7.043(3), c = 23.178(3) Å, =93.78(2)°, V = 1404.3(7) Å3; hexa-aquamanganese(II) 4-aminonaphthalene-1-sulfonate dihydrate, [Mn(H2O)6](H2NC10H6SO3)2 2H
2O: monoclinic, P21/c, Z = 2, a = 8.652(3), b = 7.031(4), c = 23.402(2) Å, =93.09(2)°, V = 1421.5(9) Å3. The structures are composed of alternating layers of octahedral metal–aqua complexes and sulfonate anions linked by an extensive network of hydrogen bonds. The extra water molecules of crystallization are located in the hexa-aquametal cation layers. The repeat unit along the c axis is a double layer. The Co and Ni compounds are isostructural with each other, but compared to the Mg and Mn compounds, have a strikingly different structure. Crystal data for hexa-aquacobalt(II) 4-aminonaphthalene-1-sulfonate trihydrate, [Co(H2O)6](H2NC10H6SO3)2 3H
2O: orthorhombic, Pbca, Z = 8, a = 8.518(1), b = 14.327(2), c = 45.367(6) Å, V = 5536(1) Å3; hexa-aquanickel(II) 4-aminonaphthalene-1-sulfonate trihydrate, [Ni(H2O)6](H2NC10H6SO3)2 3H
2O: orthorhombic, Pbca, Z = 8, a = 8.4976(6), b = 14.288(1), c = 45.076(3) Å, V = 5472.9(7) Å3. These structures also contain layers of octahedral hexa-aquametal complexes and additional water molecules of crystallization sandwiched by layers of sulfonate anions, however the stacking pattern is more complex with a quadruple layer repeat unit and two different types of anion layers. 相似文献
992.
The crystal structures of two hexammonium polymorphs, 1 and 2, and the ethane-1,2-diammonium, 3, salts of dinitramide have been determined. 1 crystallizes in the triclinic space group
with cell dimensions a = 6.391(2), b = 7.5826(9), c = 10.828(1) Å, a = 77.58(1), = 88.18 (2), = 87.54(2)°, 2 crystallizes in the monoclinic space group P21/c with cell dimensions a = 6.4893(3), b = 14.5149(8), c = 10.6557(4) Å, = 94.300(4)°, and 3 crystallizes in the triclinic space group
with cell dimensions a = 5.614(1), b = 6.867(2), c = 7.371(2) Å, = 68.89(2), = 89.00(2), = 78.90(2)°. The three structures all contain protonated amine cations which are involved in hydrogen bonding interactions with dinitramide anions. 相似文献
993.
Ram P. Kashyap Mahendra N. Deshpande Dayanada Rajapaksa Alan P. Marchand William H. Watson 《Journal of chemical crystallography》1995,25(9):573-578
Hexacyclo[6.5.0.02,7.04,12.05,10.09.13]tridecane (HCTD) contains two four-membered, two five-membered and two six-membered rings fused into a cage structure which contains about 77.0 kcal/mol of strain energy. Attempts to prepare the thioketal from the diketone of HCTD led to a skeletal rearrangement to produce a cage with one four-membered, four five-membered, and two six-membered rings fused into a cage (RHCTD). The corresponding RHCTD hydrocarbon has a strain energy 13.7 kcal/mol less than that of the starting tridecane (HCTD) which provides the driving force for the rearrangement. The X-ray structures of two HCTD derivatives and one RHCTD derivative are reported. The bond lengths in the three reported structures are normal for cages of this type. The structure of tetracyclo[6.3.0.03,7.04,11]undecane-5,10-dione mono(ketene 1,3-propanedithioacetal) is discussed also. 相似文献
994.
Hakan Arslan Donald VanDerveer Ismail Ozdemir Bekir Cetinkaya Serpil Demir 《Journal of chemical crystallography》2005,35(6):491-495
Two imidazolidin ruthenium complexes, [RuCl2{[N-(2,4,6-trimethyl-benzyl)-N-(n-butyl)]-imidazolidin-2-ylidene}], 1, and [RuCl2{[N-(2,4,6-trimethyl-benzyl)-N-(2-methoxyethyl)]-imidazolidin-2-ylidene}], 2, have been synthesised and their crystal structures have been determined from single crystal X-ray diffraction data. Compound 1 is monoclinic, of space group C2/c with a = 18.466(4) Å, b = 14.816(3) Å, c = 15.413(3) Å, β = 118.067(2)∘, and V = 3720.9(12) Å3 with Z = 8 for dcalc = 1.536 g/cm3. Compound 2 is monoclinic, of space group P21/c with a = 8.1800(5) Å, b = 14.344(8) Å, c = 14.809(9), β = 91.604(10)∘, and V = 1736.7(18) Å3 with Z = 4 for dcalc = 1.653 g/cm3. In each complex the ligand functions as an arene and carbene, occupying four coordination sites. The two chlorines in each compound complete a distorted octahedron. 相似文献
995.
Abhik?Mukhopadhyay Samudranil?PalEmail author 《Journal of chemical crystallography》2005,35(9):737-744
The syntheses, characterization and crystal structures of two mononuclear nickel(II) complexes are described. Reactions of Ni(O2CCH3)2⋅4H2O with the Schiff bases derived from 2-pyridinecarbaldehyde and ortho-aminophenol (Hpaap) and 2-pyridinecarbaldehyde and ortho-aminobenzoic acid (Hpaab) in methanolic media afford the complexes in good yields. The elemental analysis, magnetic moments, and spectral features of the complexes are consistent with the formulae [Ni(paap)2]⋅CH3COOH⋅H2O and [Ni(paab)2]⋅2H2O. Crystal data for [Ni(paap)2]⋅CH3COOH⋅H2O: monoclinic, P21/c, a = 9.675(2) Å, b = 17.109(5) Å, c = 14.403(4) Å, β = 92.903(11)∘, V = 2381.1(11) Å3, and Z = 4 and for [Ni(paab)2]⋅2H2O: triclinic, P 1, a = 9.834(3) Å, b = 11.319(3) Å, c = 13.130(4) Å, α = 84.68(3), β = 67.54(3), γ = 85.49(2)∘, V = 1343.4(6) Å3, and Z = 2. In each complex, two tridentate monoanionic meridionally spanning ligands form a distorted octahedral N4O2 coordination sphere around the metal ion. In [Ni(paap)2]⋅CH3COOH⋅H2O, two metal coordinated phenolate-O atoms are hydrogen bonded to CH3COOH and H2O, respectively. Intramolecular C–H⋅ < eqid1 > ⋅O interactions involving the water molecule and the C–H from azomethine and aromatic fragments lead to a two-dimensional network of [Ni(paap)2]⋅CH3COOH⋅H2O in the crystal lattice. An uncoordinated carboxylate O-atom in [Ni(paab)2]⋅2H2O is hydrogen bonded to both water molecules. One of the water molecules is again hydrogen bonded to the corresponding symmetry related water molecule forming a dimer. The azomethine groups and the metal coordinated carboxylate-O atoms in [Ni(paab)2] are involved in intermolecular C–H⋅ < eqid2 > ⋅O interactions forming a chain-like arrangement of the molecules. The water dimers act as bridges between these chains and a two-dimensional network of [Ni(paab)2]⋅2H2O is formed. 相似文献
996.
Paul K. Baker Michael G.B. Drew Steve P. Gonsalves Archie W. Johans Margaret M. Meehan 《Journal of chemical crystallography》2002,32(5-6):113-118
[WI2(CO)3{Ph2P(CH2)2PPh2}] (1) crystallizes out in the monoclinic space group P21/n, with a = 13.852(7) Å, b = 14.789(19) Å, c = 14.915(19) Å, = 102.86(1)°, Z = 4. [WI2(CO)3{Ph2P(CH2)3PPh2}] (2) crystallizes out in the monoclinic space group P21/n, with a = 10.499(15) Å, b = 14.58(2) Å, c = 20.75(3) Å, = 103.59(1)°, Z = 4. Both structures show the metal in a seven-coordinate environment with a carbonyl in the unique capping position, two further carbonyls and a phosphorus in the capped face, and two iodides and the second phosphorus in the uncapped face. 相似文献
997.
The crystal structures of cubane-1,4-diammonium dinitramide, 1, and cubane-1,2,4,7-tetraammonium dinitramide, 2, have been determined. 1 crystallizes in the space group P21/c with cell dimensions a = 6.018(2), b = 11.642(3), c = 9.754(3) Å, = 107.24(2), while 2 crystallizes in the space group P21/c with cell dimensions a = 9.401(4), b = 9.603(3), c = 12.603(4) Å, 111.08(3). In these structures the ammonium substituents are symmetrically attached with respect to the cubane skeleton and have neither low lying empty orbitals nor available lone pairs of electrons thus they have a minimal effect on the metrical parameters of the cubane skeleton. All C–C bond lengths are close to the overall average C–C bond length for all reported cubanes of 1.559 Å. The conformations adopted by the dinitramide ions in both structures are quite different, with the bend, twist, and torsion angles for the dinitramide ion in 1 being significantly larger than those found for the dinitramide ions in 2, due to the different types of hydrogen bonding found in the two structures. In 2, the conformation adopted by the adjacent ammonium ions allows two of the three protons from each ammonium cation to form hydrogen bonds in such a manner that they span either the syn or the anti oxygen atoms of a single dinitramide anion. The dinitramide anion is thus constrained by these interactions and is less free to twist and bend. These results provide further confirmation that the metrical parameters of both the cubane and dinitramide moieties are flexible and reflect their local environment. 相似文献
998.
The crystal structures of the hexaaquomagnesium (1), hexaaquomanganese (2), and hexaaquozinc (3) dihydrate salts of dinitramide have been determined. 1 crystallizes in the monoclinic space group P21/n with cell dimensions a = 9.589(2), b = 7.420(1), c = 11.116(2) Å, = 108.25(3)°, 2 crystallizes in the monoclinic space group P21/n with cell dimensions a = 9.623(4), b = 7.477(2), c = 11.274(3) Å, = 108.38(3)°, and 3 crystallizes in the monoclinic space group P21/n with cell dimensions a = 9.513(1), b = 7.4270(8), c = 11.164(1) Å, = 108.806(6)°. The three structures are isostructural, consisting of hexaaquo cations, dinitramide anions and water molecules interlinked by an extensive three dimensional hydrogen bonding interactions. All oxygen atoms as well as the central nitrogen atom of the dinitramide anion are involved in acceptor hydrogen bonds with neighboring water protons. As a consequence of the constraints imposed by these hydrogen bonds the dinitramide ions are almost planar with average deviations of 0.01 Å for 1, 0.03 Å for 2 and 0.03 Å for 3. 相似文献
999.
Ray J. Butcher Richard D. Gilardi Clifford George Judith Flippen-Anderson 《Journal of chemical crystallography》1996,26(6):381-388
The structures of three nitramine substituted cubane molecules, N,N-dinitro-1,4-diaminocubane (1), N,N-dinitro-N,N-(2-pyridyl)-1,4-diaminocubane (2), and 1,2,4,7-Tetrakis(N-methoxycarbonylnitramino)-cubane (3), have been determined.1 crystallized in the space group P21/a with cell dimensionsa=6.545(1),b=9.331(1),c=7.459(1) Å, =105.80(1),2 crystallized in the monoclinic space group P21/a with cell dimensionsa=7.545(2),b=8.697(3),c=12.406(4 Å, =96.28(3)°, while3 crystallized in the monoclinic space group P21/c with cell dimensionsa=10.866(3),b=6.866(2),c=16.167(6) Å, =108.79(3)°. The metrical parameters of the cubane skeleton showed no significant deviations from those found in other similarly substituted cubane molecules. For2 and3 there were considerable distortions of the nitramine moiety from planarity in contrast to1 where the nitramine moiety was almost exactly planar. The bond distances and angles for the nitramine group in1 indicates a substantial introduction of double bond character into the N–N bond in1, achieved by delocalization of the amine lone pair, compared with2 and3. 相似文献
1000.
Yoshitane Imai Dr. Katuzo Murata Kakuhiro Kawaguchi Tomohiro Sato Nobuo Tajima Dr. Reiko Kuroda Dr. Yoshio Matsubara Dr. 《化学:亚洲杂志》2008,3(3):625-629
A solid‐state fluorescent host system was created by self‐assembly of a 21‐helical columnar organic fluorophore composed of (1R,2S)‐2‐amino‐1,2‐diphenylethanol and fluorescent 1‐pyrenecarboxylic acid. This host system has a characteristic 21‐helical columnar hydrogen‐ and ionic‐bonded network. Channel‐like cavities are formed by self‐assembly of this column, and various guest molecules can be included by tuning the packing of this column. Moreover, the solid‐state fluorescence of this host system can change according to the included guest molecules. This occurs because of the change in the relative arrangement of the pyrene rings as they adjust to the tuning of the packing of the shared 21‐helical column, according to the size of the included guest molecules. Therefore, this host system can recognize slight differences in molecular size and shape. 相似文献