Reactions of the methylmercury(II) ion with adenine and crystal structure of (adeninato-N9)methylmercury (II) monohydrate

1981 ◽  
Vol 59 (9) ◽  
pp. 1311-1317 ◽  
Author(s):  
Leonardo Prizant ◽  
Marc J. Olivier ◽  
Roland Rivest ◽  
André L. Beauchamp
Keyword(s):  
Crystal Structure ◽  
Aqueous Solution ◽  
Hydrogen Bonds ◽  
Infrared Spectra ◽  
Monoclinic Space Group ◽  
Space Group ◽  
High Ph

Adenine (HAd) reacts with CH3HgX (X = NO3, ClO4) in basic aqueous solution to form a compound [CH3HgAd]•H2O, which crystallizes in the monoclinic space group C2/c, with a = 19.796, b = 7.119, c = 16.471 Å, β = 128.83°, and Z = 8. The CH3Hg+ group is linearly bonded to N(9) of deprotonated adenine and the molecules are held in pairs by two [Formula: see text] hydrogen bonds. With excess adenine, higher complexes of the formula [(CH3Hg)nAd]Xn−1(where n = 2, 3) are formed, in which positions N(9) (deprotonated), N(7), and N(3) are successively filled. Compounds [(CH3Hg)3(Ad-H)]X have been obtained at high pH by substitution of H(9) and an amino hydrogen, and with coordination of a third CH3Hg+ group probably to N(7). Complexation leads to significant changes in the infrared spectra and the 1750–1250 cm−1 regions are correlated with the substitution patterns. The structures are discussed in connection with the basicity of the donors in adenine and the basicity changes of the remaining donors when other atoms are already involved in coordination.

Ammonium Hexavanadate, (NH4)2V6O16: Preparation, Crystal Structure, Infrared Spectra and High-Pressure Reactions

1990 ◽  
Vol 45 (1) ◽  
pp. 31-38 ◽  
Author(s):  
Klaus-Jürgen Range ◽  
Christiane Eglmeier ◽  
Danita de Waal ◽  
Anton M. Heyns
Keyword(s):  
Crystal Structure ◽  
Aqueous Solution ◽  
High Pressure ◽  
Hydrogen Bonds ◽  
Infrared Spectra ◽  
Main Product ◽  
Monoclinic Space Group ◽  
Pressure System ◽  
Space Group ◽  
Deuterated Analogue

Abstract Following a re-examination of several published methods for the preparation of ammoniumhexavanadate, single crystals of (NH4)2V6O16 have been grown by a reaction of V2O5 withNH4Cl in hot aqueous solution. They are monoclinic, space group P 21/m , with a = 7.858(2),b = 8.412(2), c = 4.995(1) Å , β = 96.43(2)°, and Z = 1. The structure was refined to R = 0.060,wR = 0.039 for 745 unique reflections. It comprises layers built of V2O8 double square pyramids( V - O = 1.595- 1.988 Å) and distorted VO6 octahedra ( V - O = 1.589-2.287 Å). The infraredbands of the NH4+- and ND4+- groups in (NH4)2V6O16 and its deuterated analogue can beassigned with a fair amount of certainty at 90 K under the space group P 21/m (C2h2). The N - Dstretching modes of isotopically diluted NH3D+-groups in (NH4)2V6O16 are in agreement withthe predicted splitting into Cs, Cs and C1(2) components. The frequencies and shapes of thesemodes seem to suggest that bifurcated hydrogen bonds are formed, closely resembling the correspondingbonds in NH4VO3. The NH4+ ions are dynamic in character in (NH4)2V6O16 andremain so down to temperatures of 90 K. At high temperatures in a closed high-pressure systema redox reaction between vanadium (V ) and ammonia takes place which yields VO2 asmain product. Intermediates have been found, but up to now their com position is still unknown.

79Br, 127I NQR of Diammoniumalkyl Halides and Piperazinium Halides. Crystal Structure of Piperazinium Dibromide Monohydrate and Piperazinium Monoiodide

1989 ◽  
Vol 44 (1) ◽  
pp. 41-55 ◽  
Author(s):  
Jutta Hartmann ◽  
Shi-Qi Dou ◽  
Alarich Weiss
Keyword(s):  
Crystal Structure ◽  
Phase Transitions ◽  
Hydrogen Bonds ◽  
Crystal Structures ◽  
Monoclinic Space Group ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
Temperature Range

Abstract The 79Br and 127I NQR spectra were investigated for 1,2-diammoniumethane dibromide, -diiodide, 1,3-diammoniumpropane dibromide, -diiodide, piperazinium dibromide monohydrate, and piperazinium monoiodide in the temperature range 77 ≦ T/K ≦ 420. Phase transitions could be observed for the three iodides. The temperatures for the phase transitions are: 400 K and 404 K for 1,2-diammoniumethane diiodide, 366 K for 1,3-diammoniumpropane diiodide, and 196 K for piperazinium monoiodide.The crystal structures were determined for the piperazinium compounds. Piperazinium dibromide monohydrate crystallizes monoclinic, space group C2/c, with a= 1148.7 pm, 0 = 590.5 pm, c= 1501.6pm, β = 118.18°, and Z = 4. For piperazinium monoiodide the orthorhombic space group Pmn 21 was found with a = 958.1 pm, b = 776.9 pm, c = 989.3 pm, Z = 4. Hydrogen bonds N - H ... X with X = Br, I were compared with literature data.

scholarly journals Preparation and Crystal Structure of Zinc Bis[orotate(1–)] Octahydrate

1993 ◽  
Vol 48 (7) ◽  
pp. 961-964 ◽  
Author(s):  
Otto Kumberger ◽  
Jürgen Riede ◽  
Hubert Schmidbaur
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Medical Treatment ◽  
Single Crystal ◽  
Crystal Lattice ◽  
Structure Analysis ◽  
Monoclinic Space Group ◽  
Space Group ◽  
X Ray

A discrete zinc bis[orotate(1—)] complex of the composition Zn(OrH)2·8 H2O has been isolated and characterized by a single-crystal X-ray structure analysis. The crystals are monoclinic, space group P21/c (No. 14), Z = 2, a = 10.884(2), b = 12.896(1), c = 6.954(1) Å, β = 98.27(1)°. The crystal lattice features hexaquo complexes of zinc, the Zn(H2O)62+ cations being associated with two hydrated OrH- ions only through hydrogen bonds. The results are relevant for applications of zinc orotates in medical treatment.

The crystal structure of N-[[6-methoxy-5-(trifluoromethyl)thio-1-naphthalenyl]thioxomethyl]-N-methylglycine, C16H14F3NO3S2

1983 ◽  
Vol 61 (9) ◽  
pp. 2137-2140 ◽  
Author(s):  
Kottayil I. Varughese ◽  
Maria Przybylska ◽  
Kazimir Sestanj ◽  
Francesco Bellini ◽  
Leslie G. Humber
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Least Squares ◽  
Attractive Interaction ◽  
Monoclinic Space Group ◽  
Intermolecular Hydrogen Bonds ◽  
Space Group ◽  
Block Diagonal ◽  
Oxygen Atoms

The crystals of C16H14F3NO3S2 belong to the monoclinic space group P21/c with a = 11.577(1), b = 12.404(1), c = 12.366(1) Å, β = 90.01(1)°, and Z = 4. The structure was solved by MULTAN 78. The parameters were refined by block-diagonal least-squares to a final R of 0.047 for 2679 observed reflections. Of particular interest is an intramolecular attractive interaction between the sulfur and oxygen atoms with an [Formula: see text] distance of 2.879(2) Å, in which oxygen appears to act as an electrophile. Intermolecular hydrogen bonds between the hydroxyl and keto groups join the molecules related through a centre of symmetry into dimers.

scholarly journals Crystal structure of strontium thiosulfate monohydrate

2020 ◽  
Vol 76 (2) ◽  
pp. 197-200
Author(s):  
Wilhelm Klein
Keyword(s):  
Crystal Structure ◽  
Aqueous Solution ◽  
Hydrogen Bonds ◽  
Water Molecule ◽  
Space Group ◽  
Monodentate Ligands

SrS2O3·H2O was obtained from an aqueous solution of Na2S2O3 and Sr(NO3)2 and crystallizes in space group P\overline{1} with all atoms at general positions. The Sr2+ ion exhibits an [8 + 1] coordination defined by two terminal S and six O atoms of thiosulfate ions, one of the latter at a longer distance, and by one O atom of a water molecule. Two thiosulfate anions act as bidentate, four as monodentate ligands. The structure consists of mainly ionically interacting layers lying parallel to the crystallographic ab plane. The layers are connected by O—H...S and O—H...O hydrogen bonds of moderate strength.

Synthese und Kristallstrukturen von N-[ω-(Dimethylammonio)alkyl]- N´,N´,N´´,N´´-tetramethylguanidinium-chlorid-tetraphenylboraten / Synthesis and Crystal Structures of N-[ω-(Dimethylammonio)alkyl]-N´,N´,N´´,N´´- tetramethylguanidinium Chloride Tetraphenylborates

2010 ◽  
Vol 65 (7) ◽  
pp. 907-916 ◽  
Author(s):  
Ioannis Tiritiris ◽  
Falk Lissner ◽  
Thomas Schleid ◽  
Willi Kantlehner
Keyword(s):  
Crystal Structure ◽  
Low Temperature ◽  
Hydrogen Bonds ◽  
Crystal Structures ◽  
Room Temperature ◽  
Chloride Ions ◽  
Monoclinic Space Group ◽  
Temperature Structure ◽  
Space Group ◽  
Temperature Modification

Dicationic N,N´,N´,N´´,N´´-pentasubstituted guanidinium dichlorides 4a, b are obtained from the chloroformamidinium salt 2 and diamines 3a, b. N-[2-(Dimethylammonio)ethyl]-N´,N´,N´´,N´´-tetramethylguanidinium chloride tetraphenylborate (5a) and N-[3-(dimethylammonio)propyl]-N´,N´,N´´,N´´-tetramethylguanidinium chloride tetraphenylborate (5b) were synthesized from 4a, b by anion metathesis with one equivalent of sodium tetraphenylborate. The thermal properties of the salts 5a, b were studied by means of DSC methods, and their crystal structures were determined by single-crystal X-ray diffraction analysis. For 5a a solid-solid phase transition is observed at −156 ◦C to a low-temperature structure. The room-temperature modification (α-5a) crystallizes in the centrosymmetric orthorhombic space group Pbca (a = 13.1844(4), b = 13.8007(4), c = 34.7537(11) A° ).The guanidinium ions are interconnected via chloride ions through bridging N-H· · ·Cl hydrogen bonds, providing isolated units. The tetraphenylborate ions show some dynamic disordering in the crystal structure. The low-temperature modification (β -5a) also crystallizes orthorhombically, but in the non-centrosymmetric space group Pna21 (a = 13.1099(4), b = 69.1810(11), c = 13.5847(5) A° ) and consists of four crystallographically independent cations and anions in the unit cell. Compared with the room-temperature structure, a similar N-H· · ·Cl hydrogen bond pattern is observed in the β -phase, but the tetraphenylborate ions are now completely ordered. 5b crystallizes in the monoclinic space group P21/c (a = 10.8010(3), b = 14.1502(5), c = 20.9867(9) A° , β = 94.322(1)◦). In the crystal structure the guanidinium ions are linked via chloride ions through N-H· · ·Cl hydrogen bonds, but in contrast to 5a two infinite strands are formed along the a axis with the tetraphenylborate ions interspersed between them for charge compensation.

scholarly journals Metallkomplexe mit Guanidinderivaten als Liganden: Kristallstrukturen von [Zn(cnge)2(SCN)2] · 2H2O und Zn(eoge)Br2 (enge = Cyanoguanidin; eoge = 1-Ethoxyiminomethylguanidin) / Metal Complexes with Guanidine Derivatives as Ligands: Crystal Structures of [Zn(cnge)2(SCN)2]·2H2O und Zn(eoge)Br2 (cnge = Cyanoguanidine; eoge = 1-Ethoxyim inom ethylguanidine)

1996 ◽  
Vol 51 (10) ◽  
pp. 1469-1472 ◽  
Author(s):  
Joachim Pickardt ◽  
Britta Kühn
Keyword(s):  
Aqueous Solution ◽  
Hydrogen Bonds ◽  
Metal Complexes ◽  
Crystal Structures ◽  
Water Molecules ◽  
Monoclinic Space Group ◽  
Intermolecular Hydrogen Bonds ◽  
Crystal Water ◽  
Space Group ◽  
Guanidine Derivatives

Crystals of |Zn(cnge)2(SCN)2]-2H2O (1) were obtained by evaporation of an aqueous solution of Z n(SO4)·7H2O , KSCN, and cyanoguanidine. Crystals of Zn(eoge)Br2 (2) were obtained by reaction of ZnBr2 and cyanoguanidine in ethanol/water. Both compounds are monoclinic, space group C2/c, 1: Z = 4, a = 1919.6(7), b = 467.3(2), c = 1838.5(6) pm, β = 112.99(3)°, 2: Z = 8, a = 1799.5(6), b = 878.7(2), c = 1367.2(5) pm, β = 101.52(3)°. In 1 each Zn is bonded to two cyanoguanidine molecules and via the N atoms to two NCS groups. Intermolecular hydrogen bonds lead to chains along the a-axis, and these chains are again connected via hydrogen bonds to the two crystal water molecules. In the course of the formation of 2, the cyanoguanidine reacted with the ethanol to form 1-ethoxyiminomethylguanidine. This ligand forms chelate rings with the Zn atoms, which are tetrahedrally coordinated by the two imino N atoms of the ligand and by two bromine atoms.

scholarly journals Synthese und Struktur von Zn(HSO4)2(H2SO4)2 und Cd(HSO4)2 / Synthesis and Structure of Zn(HSO4)2(H2SO4)2 und Cd(HSO4)2

1996 ◽  
Vol 51 (1) ◽  
pp. 14-18 ◽  
Author(s):  
E. Kemnitz ◽  
C. Werner ◽  
A. Stiewe ◽  
H. Worzala ◽  
S. Trojanov
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Binary Systems ◽  
Monoclinic Space Group ◽  
Space Group ◽  
Cell Parameters ◽  
Medium Strength ◽  
Zinc Compound

Abstract From the binary systems M2SO4/H2SO4 (M = Zn, Cd), two new hydrogen sulfates, (Zn(HSO4)2(H2SO4)2 and Cd(HSO4)2, have been synthesized and structurally characterized. Both compounds crystallize in the monoclinic space group P21/c with cell parameters a = 5.047(2), b = 15.430(4), c = 7.958(3) Å and β = 104.16(4)° (Z= 2) for Zn(HSO4)2(H2SO4)2 and a = 5.339(1), b = 13.351(3), c = 8.508(2) Å and β = 92.22(3)° (Z = 4) for Cd(HSO4)2. In the zinc compound there are slightly distorted centrosymmetric ZnO6 octahedra with Zn-O distances of 2.05-2.13 A which are sharing corners with SO4 tetrahedra. HSO4 and H2SO4 tetrahedra are linked via hydrogen bonds to form layers perpendicular to the c-axis. In the crystal structure of Cd(HSO4)2 there exist two crystallographically different HSO4 tetrahedra. The CdO6 octahedra with Cd-O distances between 2.24 and 2.31 A are strongly angle-distorted. Besides hydrogen bonds of medium strength (do···o = 2.66 Å) there are also much more weaker ones (do···o = 3.04 Å). Considering these latter ones zigzag chains in z-direction can be recognized. The relatively low stability of Cd(HSO4)2 in comparison with other metal-II-hydrogen sulfates is discussed with respect to its structural pecularities.

scholarly journals Crystal structure of 1-methylimidazole 3-oxide monohydrate

2017 ◽  
Vol 73 (3) ◽  
pp. 372-374
Author(s):  
Christopher S. Frampton ◽  
James I. Murray ◽  
Alan C. Spivey
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Unit Cell ◽  
Planar Geometry ◽  
Monoclinic Space Group ◽  
Space Group ◽  
Axis Direction

1-Methylimidazole 3-N-oxide (NMI-O) crystallizes as a monohydrate, C4H6N2O·H2O, in the monoclinic space groupP21withZ′ = 2 (moleculesAandB). The imidazole rings display a planar geometry (r.m.s. deviations = 0.0008 and 0.0002 Å) and are linked in the crystal structure into infinite zigzag strands of ...NMI-O(A)...OH2...NMI-O(B)...OH2... units by O—H...O hydrogen bonds. These chains propagate along theb-axis direction of the unit cell.

scholarly journals Crystal structure of a new polymorph of (2S,3S)-2-amino-3-methylpentanoic acid

2018 ◽  
Vol 74 (6) ◽  
pp. 776-779 ◽  
Author(s):  
Sofia Curland ◽  
Elena Meirzadeh ◽  
Yael Diskin-Posner
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Monoclinic Space Group ◽  
Asymmetric Unit ◽  
Space Group ◽  
Independent Molecules

A new polymorph of (2S,3S)-2-amino-3-methylpentanoic acid, L-isoleucine C6H13NO2, crystallizes in the monoclinic space group P21 with four independent molecules in the asymmetric unit. The molecules are zwitterions. In the crystal, N—H...O hydrogen bonds link two pairs of independent molecules and their symmetry-related counterparts to form two types of layers stacked in an anti-parallel manner parallel to (001). The hydrophobic aliphatic isopropyl groups protrude from these layers.

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