Complexes of methylmercury(II) with 1-methylcytosine and crystal structure of μ-(1-methylcytosinato-N3,N4)bis(methylmercury(II)) nitrate

1981 ◽  
Vol 59 (15) ◽  
pp. 2290-2297 ◽  
Author(s):  
Leonardo Prizant ◽  
Roland Rivest ◽  
André L. Beauchamp
Keyword(s):  
Crystal Structure ◽  
Amino Group ◽  
Nitrate Salt ◽  
Acidic Media ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
H Nmr ◽  
R Factor ◽  
Nmr Data ◽  
Solid Complexes

Two types of solid complexes are isolated by reaction of CH3HgX (X = NO3 and ClO4) with 1-methylcytosine (MCy). The CH3Hg+ ion is probably bonded to N(3) in the [CH3Hg(MCy)]X compounds. Mercury binding to N(3) and the deprotonated amino group in [(CH3Hg)2(MCy—H)]X is confirmed by X-ray work on the nitrate salt. The crystals are orthorhombic, space group Pbca, with a = 12.014, b = 13.573, c = 16.353 Å, and Z = 8. The structure was refined on 962 independent reflections to an R factor of 0.038. The CH3Hg+ groups are arranged in a syn configuration and the angles around the mercury-bonded nitrogen atoms are severely distorted to prevent short Hg … Hg contacts. N(3)-coordination in the 1:1 complexes introduces minor changes in the infrared spectra, but the substitution of an amino proton in the 1:2 compounds produces important modifications. 1H nmr data in DMSO-d6 are reported for both types of compounds. This work emphasizes the important acidity enhancement experienced by the amino protons upon initial coordination to N(3), which facilitates further reaction of CH3Hg+ by proton displacement even in acidic media.

The molecular and crystal structure of [Pt(diethylenetriamine)(guanosine)](ClO4)2

1979 ◽  
Vol 57 (1) ◽  
pp. 57-61 ◽  
Author(s):  
R. Melanson ◽  
F. D. Rochon
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonding ◽  
Least Squares ◽  
Platinum Atom ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
R Factor ◽  
Square Planar ◽  
Coordination Plane

The crystal structure of [Pt(diethylenetriamine)(guanosine)](ClO4)2 has been determined by X-ray diffraction. The crystals are orthorhombic, space group P212121, with a = 12.486(6), b = 13.444(7), c = 14.678(11) Å, and Z = 4. The structure was refined by block-diagonal least-squares analysis to a conventional R factor of 0.050 and a weighted Rw = 0.045.The coordination around the platinum atom is square planar. Guanosine is bonded to platinum through N(7). The purine planar ring makes an angle of 62.7° with the platinum coordination plane. The structure is stabilized by hydrogen bonding.

Preparation and characterization of some ruthenium(II) porphyrins containing tertiary phosphine axial ligands, including the crystal structure of (octaethylporphinato)bis(triphenylphosphine)ruthenium(II)

1984 ◽  
Vol 62 (4) ◽  
pp. 755-762 ◽  
Author(s):  
Sara Ariel ◽  
David Dolphin ◽  
George Domazetis ◽  
Brian R. James ◽  
Tak W. Leung ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Phosphine Ligands ◽  
Tertiary Phosphine ◽  
X Ray ◽  
Porphyrin Complex ◽  
H Nmr ◽  
Axial Ligands ◽  
Nmr Data ◽  
Phosphine Complex

The ruthenium(II) porphyrin complex Ru(OEP)(PPh3)2 (OEP = the dianion of octaethylporphyrin) has been prepared from Ru(OEP)(CO)EtOH, and the X-ray crystal structure determined; as expected, the six-coordinate ruthenium is situated in the porphyrin plane and has two axial phosphine ligands. Synthesized also from the carbonyl(ethanol) precursors were the corresponding tris(p-methoxyphenyl)phosphine complex, and the Ru(TPP)L2 (TPP = the dianion of tetraphenylporphyrin, L = PPh3, P(p-CH3OC6H4)3, P″Bu3) and Ru(TPP)(CO)PPh3 complexes. Optical and 1H nmr data are presented for the complexes in solution. In some cases dissociation of a phosphine ligand to generate five-coordinate species occurs and this has been studied quantitatively in toluene at 20 °C for the Ru(OEP)L2 and Ru(TPP)L2 systems.

Molecular conformation of 2′-deoxy-3′,5′-di-O-acetyl adenosine. Crystal structure and high resolution proton nuclear magnetic resonance investigations

1987 ◽  
Vol 65 (2) ◽  
pp. 326-331 ◽  
Author(s):  
Leo H. Koole ◽  
Henk M. Buck ◽  
Jan A. Kanters ◽  
Arie Schouten
Keyword(s):  
Crystal Structure ◽  
Molecular Conformation ◽  
Proton Nuclear Magnetic Resonance ◽  
Solution Conformation ◽  
Orthorhombic Space Group ◽  
One Dimensional ◽  
X Ray ◽  
H Nmr ◽  
Conformational Preferences ◽  
Cell Dimensions

2′-Deoxy-3′,5′-di-O-acetyl adenosine crystallizes in the orthorhombic space group P212121, and the cell dimensions are a = 7.768(1) Å, b = 12.890(1) Å, c = 15.495(1) Å; Z = 4 molecules per cell. Least-squares refinement converged at R = 0.054 for 1752 observed reflections. The adenine bases are linked via N6—H … N1 and N6—H … N7 hydrogen bonds, in such a way that infinite one-dimensional chains are formed. Comments are made on the fact that this structure is entirely different from the parallel dimer that was found for 3′,5′-di-O-acetyl thymidine. Furthermore, the conformational preferences of the title compound in aqueous solution have been determined with 300- and 500-MHz 1H nmr. It is found that the X-ray structure and the solution conformation are essentially similar, except for the C4′—C5′ conformation, that is γ− in the solid state, and predominantly γ+ in solution.

scholarly journals Pressure-induced polymorphism in cyclopropylamine

2005 ◽  
Vol 61 (6) ◽  
pp. 717-723 ◽  
Author(s):  
Patricia Lozano-Casal ◽  
David R. Allan ◽  
Simon Parsons
Keyword(s):  
Crystal Structure ◽  
Crystal Packing ◽  
Hirshfeld Surface ◽  
Amino Group ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
Cell Dimensions ◽  
Graph Set ◽  
Unit Cell Dimensions

The crystal structure of cyclopropylamine at 1.2 GPa has been determined by X-ray diffraction methods. The structure of this phase is orthorhombic, space group Pbca and the unit-cell dimensions are a =  5.0741 (10), b  =  9.7594 (10) and c  =  13.305 (2) Å. Only one of the two H atoms of the amino group actively participates in the formation of the hydrogen-bonded chains, C(2) in graph-set notation, which lie parallel to the crystallographic a axis. Additionally, the topology of the crystal packing is studied using both Voronoi–Dirichlet polyhedra and Hirshfeld surface analyses for the low-temperature and the high-pressure structures of cyclopropylamine and the results are compared.

Binding sites between palladium(II) and nucleosides or nucleotides and crystal structure of [Pd(diethylenetriamine)(guanosine)](ClO4)2

1980 ◽  
Vol 58 (4) ◽  
pp. 381-386 ◽  
Author(s):  
F. D. Rochon ◽  
P. C. Kong ◽  
B. Coulombe ◽  
R. Melanson
Keyword(s):  
Crystal Structure ◽  
Binding Sites ◽  
Palladium Atom ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
R Factor ◽  
Square Planar ◽  
Purine Ring ◽  
Coordination Plane

The interactions between [Pd(dien)Cl]Cl and some nucleosides and nucleotides were studied by nmr. The binding site of guanosine, guanosinemonophosphoric acid, xanthosine, and inosine is N(7). Cytidine is coordinated to palladium through N(3). Adenosinemonophosphate acts as a bidentate, binding two different palladium atoms at N(1) and N(7).The crystal structure of [Pd(dien)(guanosine)](ClO4)2 has been determined by X-ray diffraction. The crystals are orthorhombic, space group P212121, with a = 13.422, b = 14.587, c = 12.432, and Z = 4. The structure was refined by block-diagonal least-squares analysis to a conventional R factor of 0.047 and a weighted Rw = 0.043. The coordination around the palladium atom is square planar. Guanosine is bonded to palladium through N(7). The planar purine ring makes an angle of 63.4° with the palladium coordination plane. The structure is stabilized by hydrogen bonding.

Preparation and characterization of some ruthenium(III) porphyrins, including the crystal structure of bromo(octaethylporphinato)(triphenylphosphine)ruthenium(III)

1984 ◽  
Vol 62 (7) ◽  
pp. 1239-1245 ◽  
Author(s):  
Brian R. James ◽  
David Dolphin ◽  
T. W. Leung ◽  
Frederick W. B. Einstein ◽  
Anthony C. Willis
Keyword(s):  
Crystal Structure ◽  
Cation Radical ◽  
Hydrogen Halides ◽  
X Ray ◽  
Radical Intermediates ◽  
H Nmr ◽  
Nmr Data ◽  
Paramagnetic Shifts

Some ruthenium(III) complexes Ru(porp)(L)X and [Ru(porp)L2]X, (porp = dianion of octaethylporphyrin (OEP) or tetraphenylporphyrin (TPP); L = PPh3, P″Bu3; X = Br, Cl) have been prepared from the precursor complexes Ru(porp)L2 or Ru(porp)(CO)L using as oxidant the halogens, or air in the presence of the hydrogen halides. The X = PF6 salts can be made using Et3O+PF6− as oxidant. Ruthenium(II) porphyrin π-cation radical intermediates have sometimes been detected. The X-ray crystal structure of Ru(OEP)(PPh3)Br, the first reported for a ruthenium(III) porphyrin, reveals that metal is displaced 0.049 Å from the plane of the pyrrole N atoms towards the phosphine. The Ru(OEP)(py) Br and [Ru(OEP)(py)CH3CN]PF6 complexes have been synthesized from Ru(OEP)(CO)py. The ruthenium(III) complexes are low-spin as shown by magnetic and esr data. Optical and 1H nmr data, the latter showing large paramagnetic shifts, are also presented.

Étude structurale d'un C-glycoside insaturé; le tri-O-acétyl-3,4,6-désoxy-2-α-D-thréo-hexéno-2-pyrannosyle benzène

1985 ◽  
Vol 63 (2) ◽  
pp. 491-494 ◽  
Author(s):  
Hélène Gillier-Pandraud ◽  
Rachid Brahmi ◽  
Véronique Bellosta-Dechavanne ◽  
Stanislas Czernecki
Keyword(s):  
Aromatic Ring ◽  
Crystalline State ◽  
Crystallographic Data ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
H Nmr ◽  
Sugar Moiety ◽  
Nmr Data ◽  
Anomeric Carbon

The structure of 3,4,6-tri-O-acetyl-2-deoxy-α-D-threo-hexeno-pyranosyl benzene 1 has been determined by X-ray diffraction methods. Crystals of 1 are orthorhombic, space group P212121 with a = 22.946(10), b = 10.319(6), c = 7.684(4) Å, V = 1819.42 Å3, Z = 4, ρc = 1.27 g cm−3. The sugar moiety exhibits a half-chair 0H5 conformation in which the aromatic ring is quasi-axial. The anomeric carbon has the α. configuration. The comparison of the 1H nmr data with the crystallographic data established that, in solution, the conformation of 1 is very similar to that in the crystalline state.

1,2-Bis-(1-{3-pyridyl-}3-methyltriazen-3-yl)ethane: Synthesis and X-ray crystal structure

2004 ◽  
Vol 82 (3) ◽  
pp. 448-453 ◽  
Author(s):  
Keith Vaughan ◽  
Elizabeth Turner ◽  
Hilary Jenkins
Keyword(s):  
Crystal Structure ◽  
Diazonium Salt ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
Temperature Spectrum ◽  
X Ray ◽  
H Nmr ◽  
Antitumour Agent ◽  
Room Temperature Spectrum ◽  
Conventional Manner

3-Aminopyridine is diazotized in the conventional manner and the diazonium salt coupled with N,N ′-dimethylethylenediamine to afford the title compound (1), which is a potential antitumour agent. The compound has been characterized by spectroscopic methods. The 1H NMR spectrum shows evidence of rotational conformerism, from the observation of broadening of the N-methyl signals in the room-temperature spectrum. Low-temperature NMR spectra (down to 223 K) show the presence of three distinct rotamers. The crystal structure of 1,2-bis-(1-{3-pyridyl-}3-methyltriazen-3-yl)ethane (1) has been determined by single crystal X-ray diffraction analysis. The bis-triazene (1) exists as the "staggered" conformation in the solid state, with an "anti–anti" configuration around the N—N bond of the triazene units. The crystal structure of 1 is compared with the closely related bis-triazene 2 and also compared with the simple mono-triazene 3. Crystal data for 1, C14H18N8: orthorhombic, space group Pbca, a = 11.2550(8) Å, b = 8.8507(6) Å, c = 15.0069(10) Å, β = 90°, and V = 1494.91(18) Å3, for Z = 4.Key words: triazene, bis-triazene, pyridine, X-ray, VT NMR, diazonium coupling.

scholarly journals Chemie polyfunktioneller Moleküle, 106. Kupfer(I)halogenid — Komplexe des Bis(diphenylphosphino)amins / Chemistry of Polyfunctional Molecules, 106. Copper(I) Halide Complexes of Bis(diphenylphosphino)amine

1990 ◽  
Vol 45 (12) ◽  
pp. 1657-1668 ◽  
Author(s):  
Jochen Ellermann ◽  
Falk A. Knoch ◽  
Klaus J. Meier
Keyword(s):  
Crystal Structure ◽  
Mass Spectra ◽  
Nmr Spectra ◽  
Conductivity Data ◽  
Triclinic Space Group ◽  
X Ray ◽  
Lattice Constants ◽  
H Nmr ◽  
Nmr Data ◽  
Halide Complexes

Reaction of Copper(I) halides CuX (X = Cl, Br, I) in methanol with bis(diphenylphosphino)amine (dppa, 1) yields complexes [Cu3X2(dppa)3]X (X = Cl, Br, I: 2a–c). The derivates [Cu3X2(dppa)3]PF6 (2a′–c′) have been synthesized by metatheses of 2a–c with NH4PF6. The IR, Raman, 31P{1H} NMR, 1H{31Ρ} NMR, 13C{1H} NMR spectra, and FD mass spectra as well as the conductivity data are reported and discussed together with the X-ray crystal structure of 2a · 5 CH3OH. The structure consists of the trinuclear cations [Cu3Cl2(dppa)3]+, distorted tetrahedral anions [Cl( · · · HOCH3)4]- and molecules of methanol of crystallization, hydrogen bridged to the solvated anions. The Cu3Cl2 core of the cations corresponds closely to a trigonal bipyramid with the copper atoms in the equatorial and the chlorine atoms in the axial positions. The colourless prisms of 2a · 5 CH3OH crystallize in the triclinic space group P1̅, with the lattice constants a = 1368.0(4); b = 1486.7(4); c = 2036.8(10) pm; α = 74.52(3); β = 74.73(3); γ = 82.26(2)°. Raman and 31P{1H} NMR data of the complexes [Cu(X)dppm]4 (dppm = (C6H5)2PCH2P(C6H5)2; X = Br, I) described earlier suggest that these compounds should also be formulated as [Cu3X2(dppm)3]X (4b, c).The Raman spectra of the cations of 2a–c, 2a′–c′ and 4a–c show bands at 165 (X = Cl), 145 (X = Br) and 125 (X = I) cm-1, which can be assigned to the symmetric (XCu3X) stretching mode of the XCu3X unit.

Synthesis of complexes of the type cis-Pt(amine) (unsaturated ligand)Cl2 and crystal structure cis-Pt(methylaimne) (dimethylhexynediol)Cl2

1989 ◽  
Vol 67 (12) ◽  
pp. 2209-2212 ◽  
Author(s):  
F. D. Rochon ◽  
R. Melanson ◽  
Monique Doyon
Keyword(s):  
Crystal Structure ◽  
Platinum Complexes ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Methyl Derivative ◽  
Full Matrix ◽  
X Ray ◽  
H Nmr ◽  
R Factor ◽  
Square Planar

Complexes of the type cis-Pt(L)(un)Cl2 where L = primary amine or methyl derivative of pyridine and un = cyclopentene, cyclohexene, or dimethylhexynediol, have been synthesized from the reaction of K[Pt(L)Cl3] with the unsaturated ligand in water. The compounds were characterized and studied by 1H NMR and IR spectroscopy. The crystal structure of cis-Pt(CH3NH2)((CH3)2C(OH)—C≡C—C(OH)(CH3)2)Cl2 was determined by X-ray diffraction methods. The crystals are monoclinic, space group P21/c, with a = 6.544(2), b = 14.304(7), c = 15.508(7) Å, β = 109.39(2)°, and Z = 4. The coordinates and the anisotropic thermal factors were refined by full-matrix least-squares analysis to a R factor of 0.048 and wR = 0.047. The coordination around the platinum atom is square planar and the acetylenic ligand is perpendicular to the Pt plane. Keywords: platinum complexes, crystal structure, methylamine, dimethylhexynediol, synthesis.

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