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Strong O (strong + o)
Selected AbstractsA novel (3,4,10)-connected three-dimensional hydrogen-bonded supramolecular network containing a cyclic water hexamerACTA CRYSTALLOGRAPHICA SECTION C, Issue 6 2009Yan Zhou The title compound, 4,4,-(1,1,1,3,3,3-hexafluoroisopropylidene)diphthalic acid hexahydrate, C19H10F6O8·6H2O, crystallizes in the centrosymmetric space group Pbcn, with half of the diphthalic acid residue and three water molecules in the asymmetric unit. The organic molecule is located on a crystallographic twofold axis. In the solid, cyclic water hexamers in chair conformations have crystallographically imposed inversion symmetry. Strong O,H...O hydrogen bonds between the hexamers and organic molecules result in a unique three-dimensional supramolecular network [O...O = 2.554,(2),2.913,(2),Å]. This compound represents the first example of a (3,4,4,10)-connected four-nodal supramolecular topology with the Schläfli symbol (43.5.6.7)2(43.52.7)2(43)2(46.56.62.78.814.99). [source] Migration of the proton in the strong O,H,O hydrogen bond in urea,phosphoric acid (1/1)ACTA CRYSTALLOGRAPHICA SECTION B, Issue 3 2001Chick C. Wilson The structure of urea,phosphoric acid is reported at a large number of temperatures in the range 150,335,K from neutron diffraction data collected using a novel multiple single-crystal data collection method. The work focuses on the behaviour of the H atom involved in the short strong O,H,O hydrogen bond in this material. The position of this atom is shown to vary significantly, by around 0.035 ,Å, as a function of temperature, becoming effectively centred at the highest temperatures studied. This result, only accessible due to the accurate determination of H-atom parameters by neutron diffraction, has implications for the potential governing the hydrogen bond. [source] Two cobalt(III) mono-dimethylglyoximates isolated from one reactionACTA CRYSTALLOGRAPHICA SECTION C, Issue 9 2010Agnieszka Czapik The reaction of cobalt(II) nitrate hexahydrate with dimethylglyoxime (DMGH2) and 1,10-phenanthroline (phen) in a 1:1:2 molar ratio results in two CoIII mono-dimethylglyoximates having two chelating phen ligands in cis positions and the CoIII atom coordinated by six N atoms in a distorted octahedral coordination geometry. The isolated products differ in the deprotonation state of the DMGH2 ligand. In [,-hydrogen bis(N,N,-dioxidobutane-2,3-diimine)]tetrakis(1,10-phenanthroline)cobalt(III) trinitrate ethanol disolvate 1.87-hydrate, [Co2(C4H6N2O2)(C4H7N2O2)(C12H8N2)4](NO3)3·2C2H6O·1.87H2O, (I), the C2 -symmetric cation is formed with the coordination [Co(DMG)(phen)2]+ cations aggregating via a very strong O,...H+...O, hydrogen bond with an O...O distance of 2.409,(4),Å. Crystals of (I) exhibit extensive disorder of the solvent molecules, the nitrate anions and one of the phen ligands. Compound (I) is a kinetic product, not isolated previously from similar systems, that transforms slowly into (N -hydroxy- N,-oxidobutane-2,3-diimine)bis(1,10-phenanthroline)cobalt(III) dinitrate ethanol monosolvate 0.4-hydrate, [Co(C4H7N2O2)(C12H8N2)2](NO3)2·C2H6O·0.40H2O, (II), with the DMGH, ligand hydrogen bonded to one of the nitrate anions. In (II), the solvent molecules and one of the nitrate anions are disordered. [source] 25-Allyloxy-5,11,17,23-tetra- tert -butyl-26,27,28-trihydroxycalix[4]arene chloroform disolvateACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2010Tobias Gruber In the title solvated calixarene, C47H60O4·2CHCl3, the host chalice displays an almost undistorted cone conformation, stabilized by three strong O,H...O hydrogen bonds at the calixarene's lower rim. One chloroform solvent molecule is fixed in the calixarene cavity by C,H..., interactions, while the second is accommodated in a clathrate-like mode in elliptical packing voids. These voids are spanned by six host molecules connected via C,H..., contacts and van der Waals interactions. Within the crystal structure, one tert -butyl group of the calixarene host is disordered over two orientations, with occupancies of 0.884,(4) and 0.116,(4). Furthermore, both solvent molecules show disorder, with occupancies of 0.857,(2) and 0.143,(2) for the cavitate-type, and 0.9359,(17) and 0.0641,(17) for the clathrate-type chloroform solvent molecules. [source] 4-Chloro-1-naphtholACTA CRYSTALLOGRAPHICA SECTION C, Issue 5 2009Ewa Rozycka-Sokolowska Molecules of the title compound, C10H7ClO, (I), are connected by a single strong O,H...O hydrogen bond into a simple C(2) chain, which runs parallel to the c axis and is additionally stabilized by intermolecular ,,, stacking interactions. The significance of this study lies in the comparison drawn between the crystal structure of (I) and those of several of its simple analogues. This comparison shows a close similarity in the packing of the molecules that form ,-stacks along the shortest crystallographic axes. A substantial spatial overlap is observed between adjacent molecules in such a ,-stack, depending mainly on the kind of substituent. [source] Mo4(,3 -allyl)4Cl2(OH)2(CO)8: the first cubane-type Mo2+ organometallic complex with ,3 -OH and ,3 -Cl bridgesACTA CRYSTALLOGRAPHICA SECTION C, Issue 4 2009Tatiana R. Amarante The reaction between fluorenyllithium and Mo(,3 -C3H5)Cl(NCMe)2(CO)2 led to the isolation of di-,3 -chlorido-di-,3 -hydroxido-tetrakis[(,3 -allyl)dicarbonylmolybdenum(II)],9-fluorenone,tetrahydrofuran (1/1/1), [Mo4(C3H5)4Cl2(OH)2(CO)8]·C4H8O·C13H8O. The tetrametallic Mo4 unit constitutes the first example of a complex containing simultaneously two ,3 -OH groups and two ,3 -Cl anions capping the metallic trigonal prism. The four crystallographically independent Mo2+ centres exhibit distorted octahedral geometry with the ,3 -allyl groups being trans -coordinated to a ,3 -OH group and the carbonyl groups occupying the equatorial plane. Space-filling tetrahydrofuran and 9-fluorenone molecules are engaged in strong O,H...O hydrogen-bonding interactions with Mo4(,3 -allyl)4Cl2(OH)2(CO)8 complexes. [source] 3,3,,5,5,-Tetramethyl-4,4,-bipyrazole,pentafluorophenol (2/3)ACTA CRYSTALLOGRAPHICA SECTION C, Issue 6 2008Konstantin V. Domasevitch In the title compound, 2C10H14N4·3C6HF5O, one of the pentafluorophenol molecules resides on a mirror plane bisecting the O...F axis. The components aggregate by N,H...N, N,H...O and O,H...N hydrogen bonds involving equal disordering of the H atoms into molecular ensembles based on a 2:1 pyrazole,phenol cyclic pattern [O...N = 2.7768,(16),Å and N...N = 2.859,(2),Å], crosslinked into one-dimensional columns via hydrogen bonding between the outer pyrazole groups and additional pentafluorophenol molecules. The latter yields a 1:1 pyrazole,phenol catemer with alternating strong O,H...N [2.5975,(16),Å] and weaker N,H...O [2.8719,(17),Å] hydrogen bonds. This is the first reported molecular adduct of a pentafluorinated phenol and a nitrogen base, and suggests the utility of highly acidic phenols and pyrazoles for developing hydrogen-bonded cocrystals. [source] Cocrystallization and configurations of myo -inositol-1,2- l -camphor acetals in two crystal structuresACTA CRYSTALLOGRAPHICA SECTION C, Issue 3 2007Graeme J. Gainsford The inositol rings in (1S,2R,3R,4S,5S,6R,7S,8S,11S)- myo- inositol-1,2-camphor acetal {systematic name: (1R,2S,3S,4R,5S,6R)-5,6-[(1S,2S,4S)-1,7,7-trimethylbicyclo[2.2.1]heptane-2,2-diyldioxy]cyclohexane-1,2,3,4-tetrol}, C16H26O6, and (1R,2S,3S,4R,5R,6S,7R/S,8S,11S)- myo -inositol-1,2-camphor acetal trihydrate {systematic name: (1S,2R,3R,4S,5R,6S)-5,6-[(1S,4S,6R/S)-1,7,7-trimethylbicyclo[2.2.1]heptane-2,2-diyldioxy]cyclohexane-1,2,3,4-tetrol trihydrate}, C16H26O6·3H2O, adopt flattened chair conformations with the latter crystal containing two stereoisomers in a 0.684,(2):0.316,(2) ratio, similar to that found both in solution and by calculation. Both molecules pack in the crystals in similar two-dimensional layers, utilizing strong O,H,O hydrogen bonds, with the trihydrate cell expanded to incorporate the additional hydrogen-bonded water molecules. [source] | ||||||||||