Crystal and molecular structure of the m-bromobenzoate derivative of bisnorquassin

1970 ◽  
Vol 48 (2) ◽  
pp. 307-311 ◽  
Author(s):  
H. Lynton
Keyword(s):  
Molecular Structure ◽  
Crystal And Molecular Structure ◽  
Heavy Atom ◽  
Unit Cell ◽  
Anisotropic Temperature ◽  
Cell Dimensions ◽  
Final Agreement ◽  
Unit Cell Dimensions ◽  
Heavy Atom Method ◽  
Atomic Parameters

The molecular structure of the m-bromobenzoate derivative of bisnorquassin, C27H27O7Br, has been determined by the heavy atom method. The compound crystallizes in the orthorhombic system, space group P212121, with unit cell dimensions a = 20.09 ± 0.02 Å, b = 14.63 ± 0.02 Å, c = 8.06 + 0.01 Å and 4 molecules in the unit cell. Final atomic parameters have been obtained from a blockdiagonal least-squares refinement using anisotropic temperature parameters. The final agreement residual for 1665 observed reflections is R = 0.107.The structure of bisnorquassin previously proposed by Findlay and Cropp, on the basis of spectroscopic and chemical evidence, is shown to be essentially correct.

Crystal and Molecular Structure of 2-Bromo-11-ethyl-5,9-dimethoxytetracyclo[5.4.1.14,12•18,11]tetradecan-3-one, C18H27BrO3

1971 ◽  
Vol 49 (15) ◽  
pp. 2497-2500 ◽  
Author(s):  
R. F. Dunphy ◽  
H. Lynton
Keyword(s):  
Molecular Structure ◽  
Crystal And Molecular Structure ◽  
Heavy Atom ◽  
Unit Cell ◽  
Monoclinic System ◽  
Cell Dimensions ◽  
Final Agreement ◽  
Unit Cell Dimensions ◽  
Heavy Atom Method ◽  
Atomic Parameters

The molecular structure of 2-bromo-11-ethyl-5,9-dimethoxytetracyclo[5.4.1.14,12•18,11]tetradecan-3-one, C18H27BrO3, synthesized in an attempt to develop a method of conversion from an advanced relay compound to the alkaloid delphinine, has been determined by the heavy atom method. The compound crystallizes in the monoclinic system, space group P21/c, with unit cell dimensions a = 9.684(9), b = 13.481(15), c = 12.988(14) Å, β = 99.47(7)°, and four molecules in the unit cell. The atomic parameters were refined by block-diagonal least squares using anisotropic thermal parameters. The hydrogen atom positions were established but the parameters were not refined. The final agreement residual for 816 observed reflections is R = 0.044.The stereochemistry of the compound was found to be unsuitable for the delphinine synthesis.

scholarly journals Crystal and Molecular Structure of the 1:1 Complex of Chloral Hydrate and 7-Bromo-2,3-dihydro-1-methyl-5-phenyl-1,4-benzodiazepin-2-one

1971 ◽  
Vol 49 (20) ◽  
pp. 3401-3404 ◽  
Author(s):  
R. F. Dunphy ◽  
H. Lynton
Keyword(s):  
Chloral Hydrate ◽  
Crystal And Molecular Structure ◽  
Heavy Atom ◽  
Unit Cell ◽  
Orthorhombic System ◽  
Cell Dimensions ◽  
Final Agreement ◽  
Unit Cell Dimensions ◽  
Heavy Atom Method ◽  
Atomic Parameters

The structure of a 1:1 complex of chloral hydrate and 7-bromo-2,3-dihydro-1-methyl-5-phenyl-1,4-benzodiazepin-2-one has been determined by the heavy atom method. The complex crystallizes in the orthorhombic system, space group Pbca, with unit cell dimensions a = 13.45(1), b = 26.74(2), c = 11.23(1) Å and 8 molecules in the unit cell. The 1:1 complex of chloral hydrate and diazepam, 7-chloro-2,3-dihydro-1-methyl-5-phenyl-1,4-benzodiazepin-2-one, is isomorphous with the above compound and has unit cell dimensions a = 13.43(1), b = 26.60(2), c = 11.20(1) Å. The final atomic parameters have been obtained from a block-diagonal least squares refinement using anisotropic thermal parameters. The final agreement residual for 575 observed reflections is R = 0.079.The structure consists of chains of chloral hydrate and Br-diazepam molecules linked by hydrogen bonds.

Crystal and molecular structure of CuSiF6•4H2O

1969 ◽  
Vol 47 (20) ◽  
pp. 3859-3861 ◽  
Author(s):  
M. J. R. Clark ◽  
J. E. Fleming ◽  
H. Lynton
Keyword(s):  
Molecular Structure ◽  
Least Squares ◽  
Fluorine Atom ◽  
Crystal And Molecular Structure ◽  
Unit Cell ◽  
Space Group ◽  
Anisotropic Temperature ◽  
Cell Dimensions ◽  
Final Agreement ◽  
Atomic Parameters

The structure of CuSiF6•4H2O has been shown to consist of chains of [Cu(H2O)4F2] and [SiF6] octahedra linked through a common fluorine atom. The space group is monoclinic P21/a, with cell dimensions a = 7.22 ± 0.01 Å, b = 9.64 ± 0.01 Å, c = 5.36 ± 0.01 Å and β = 105.2 ± 0.3°. There are 2 molecules in the unit cell and the copper and silicon atoms occupy centers of symmetry. Atomic parameters have been obtained from a block diagonal least squares refinement using anisotropic temperature parameters. The final agreement residual for 574 observed reflections is R = 0.083.

scholarly journals The crystal and molecular structure of the bis(N,N,N′,N′-tetramethylethanediamine) adduct of I(Br)InInBr2, In2Br3I•2C6H16N2, an indium–indium bonded molecule

1984 ◽  
Vol 62 (3) ◽  
pp. 601-605 ◽  
Author(s):  
Masood A. Khan ◽  
Clovis Peppe ◽  
Dennis G. Tuck
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Crystal And Molecular Structure ◽  
Heavy Atom ◽  
Orthorhombic Space Group ◽  
Trigonal Bipyramidal ◽  
Cell Dimensions ◽  
Unit Cell Dimensions ◽  
Heavy Atom Method ◽  
Distorted Trigonal Bipyramidal

The crystal structure of the title compound has been determined by the heavy atom method. The crystals are orthorhombic, space group Pbca, with unit cell dimensions a = 22.795(3) Å, b = 17.518(2) Å, c = 12.396(3) Å, Z = 8; R = 0.0409 for 1527 unique "observed" reflections. The structure is disordered, with each halogen site (X) occupied by 75% Br, 25% I. The molecule consists of two X2(tmen)In units (tmen = N,N,N′,N′-tetramethylethanediamine) with distorted trigonal bipyramidal geometry, joined by an In—In bond 2.775(2) Å in length.

Crystal and Molecular Structure of Hexaaquocobalt(II)–Hexafluorosilicate(IV), [Co(H2O)6][SiF6]

1973 ◽  
Vol 51 (2) ◽  
pp. 227-229 ◽  
Author(s):  
H. Lynton ◽  
P-Y. Siew
Keyword(s):  
Molecular Structure ◽  
Hydrogen Atom ◽  
Hydrogen Bonds ◽  
Least Squares ◽  
Crystal And Molecular Structure ◽  
Heavy Atom ◽  
Thermal Parameters ◽  
Final Agreement ◽  
Heavy Atom Method ◽  
Atomic Parameters

The structure of hexaaquocobalt(II)-hexafluorosilicate(IV) has been determined by the heavy atom method. The compound crystallizes in the space group [Formula: see text], with three molecules in the hexagonal unit cell of dimensions a = 9.358(16), c = 9.712(14) Å. The atomic parameters were refined by block diagonal least squares using anisotropic thermal parameters. The hydrogen atom positions were established but the parameters were not refined. The final agreement residual for 151 observed reflections is R = 0.043.The structure consists of discrete Co(H2O)62+ and (SiF6)2− octahedra joined systematically by [Formula: see text] hydrogen bonds into chains parallel to the [Formula: see text] axis.

The Crystal and Molecular Structure of sym-fac-(1,4,7-Triazaheptane)-(S)-aspartatocobalt(III) Diperchlorate Dihydrate

1994 ◽  
Vol 59 (5) ◽  
pp. 1052-1058 ◽  
Author(s):  
Jan Ondráček ◽  
Jana Ondráčková ◽  
Jaroslav Maixner ◽  
František Jursík
Keyword(s):  
Molecular Structure ◽  
Aspartic Acid ◽  
Crystal And Molecular Structure ◽  
Heavy Atom ◽  
Membered Ring ◽  
Boat Conformation ◽  
Hydrogen Atoms ◽  
Orthorhombic System ◽  
Anisotropic Temperature ◽  
Heavy Atom Method

The crystal and molecular structure of s-fac-[Co((S)-Asp)(dien)]ClO4 . HClO4 .2 H2O (dien = 1,4,7-triazaheptane) was solved by the heavy atom method. The position parameters of the non-hydrogen atoms and their anisotropic temperature parameters were refined based on 1 726 observed reflections with a final value of R = 0.073. The substance crystallizes in the orthorhombic system in the space group P212121, Z = 4, a = 8.506(1), b = 17.171(2), c = 13.277(1) Å. The structure involves hydrogen bonds between the O2, O4 and HN2 atoms of aspartic acid and the two molecules of water. The five-membered dien chelate rings take the asymmetric envelope conformations. The five-membered ring of (S)-aspartic acid possesses the symmetric envelope conformation whereas the six-membered ring exhibits the skew boat conformation.

Determination of the structure of bis(propyldithiocarbamate)nickel(II)

1990 ◽  
Vol 55 (4) ◽  
pp. 1010-1014 ◽  
Author(s):  
Jiří Kameníček ◽  
Richard Pastorek ◽  
František Březina ◽  
Bohumil Kratochvíl ◽  
Zdeněk Trávníček
Keyword(s):  
Molecular Structure ◽  
Title Compound ◽  
Crystal And Molecular Structure ◽  
Heavy Atom ◽  
Unit Cell ◽  
Monoclinic Space Group ◽  
Planar Configuration ◽  
Compound C ◽  
Heavy Atom Method

The crystal and molecular structure of the title compound (C8H16N2NiS4) was solved by the heavy atom method and the structure was refined anisotropically to a final R factor of R = 0.029 (wR = 0.037) for 715 observed reflections. The crystal is monoclinic, space group P21/c with a = 948.3(2), b = 776.9(2), c = 1 167.4(2) pm, β = 125.14(2)°, Z = 2. The molecule contains two four-membered NiSCS rings of approximately planar configuration with the Ni atom situated at a centre of symmetry. The molecules are arranged in chains along the c-axis of the unit cell.

Crystal and Molecular Structure of the s-fac-[Co((S)-Asp)(medien)]ClO4 . H2O . HClO4 Isomer

1993 ◽  
Vol 58 (2) ◽  
pp. 335-342 ◽  
Author(s):  
Jan Ondráček ◽  
Jaroslav Maixner ◽  
Jana Ondráčková ◽  
František Jursík
Keyword(s):  
Molecular Structure ◽  
Crystal And Molecular Structure ◽  
Chelate Ring ◽  
Complex Cation ◽  
Heavy Atom ◽  
Boat Conformation ◽  
Membered Chelate Ring ◽  
Anisotropic Temperature ◽  
Hydroxonium Cation ◽  
Heavy Atom Method

The crystal and molecular structure of s-fac-[Co((S)-Asp)(medien)]ClO4 . H2O . HClO4 was elucidated by the heavy atom method. The positional parameters of the nonhydrogen atoms and their anisotropic temperature parameters were refined based on 2 474 observed reflection with final values of R = 0.0603 and wR = 0.0616. The substance crystallized in the orthorhombic system in the space group P212121, Z = 4, a = 8.536(1), b = 13.378(1), c = 16.899(2) Å. The structure comprises layers of the complex cation which alternate with layers containing two perchlorate anions and one hydroxonium cation. The five-membered chelate ring of 4-methyl-1,4,7-triazaheptane exist in the asymmetric λ, δ envelope conformations and the N-CH3 group of the triamine has the exo orientation. The five-membered ring of (S)-aspartic acid assumes the symmetric envelope conformation, the six-membered chelate ring, the skew boat conformation.

Crystal structure of diethylammonium tetrachloro(p-phenoxyphenyl)tellurate

1984 ◽  
Vol 62 (1) ◽  
pp. 32-35 ◽  
Author(s):  
Raj K. Chadha ◽  
John E. Drake ◽  
Masood A. Khan
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonding ◽  
Heavy Atom ◽  
Unit Cell ◽  
Monoclinic Space Group ◽  
Secondary Interaction ◽  
Cell Dimensions ◽  
Unit Cell Dimensions ◽  
Heavy Atom Method ◽  
Interionic Hydrogen

The crystal structure of diethylammonium tetrachloro(p-phenoxyphenyl)tellurate has been determined by the heavy atom method. The crystals are monoclinic, space group C2/c, with unit cell dimensions a = 19.675(5), b = 7.634(3), c = 28.716(6) Å, β = 105.58(2)°, and Z = 8. For 2636 "observed" reflections (I > 3σ(I)), R = 0.030. The primary geometry about tellurium is based on a square pyramid with a secondary interaction on the vacant side of the tellurium coordination octahedron. The ions are apparently linked by weak interionic hydrogen bonding along the crystallographic b axis.

Crystal and Molecular Structure of the Synthetic Intermediate, 2-Bromo-3-methoxy-5-hydroxy-5,6,7,8,9,10,13,14-octahydro-8-methyl-10,13-N-acetylaminomethano-phenanthrene, C19H24O3NBr

1973 ◽  
Vol 51 (16) ◽  
pp. 2637-2638 ◽  
Author(s):  
H. Lynton ◽  
P. Y. Siew
Keyword(s):  
Crystal And Molecular Structure ◽  
Heavy Atom ◽  
Monoclinic Space Group ◽  
Asymmetric Unit ◽  
Full Matrix ◽  
Cell Dimensions ◽  
Ring Nitrogen ◽  
Unit Cell Dimensions ◽  
Synthetic Intermediate ◽  
Heavy Atom Method

Crystals of the synthetic intermediate, 2-bromo-3-methoxy-5-hydroxy-5,6,7,8,9,10,13,14-octahydro-8-methyl-10,13-N-acetyl aminomethano-phenanthrene, C19H24O3NBr, are monoclinic, space group P21/n, unit cell dimensions a = 10.62(1), b = 14.47(2), c = 23.88(2) Å, β = 99.4(2)°, z = 8 with two molecules in the asymmetric unit. The structure was solved by the heavy atom method and refined by full matrix least squares to R = 0.096 for 2120 observed reflections. The conformation was found to be cis at the junction between rings A and B making further cyclization to obtain an A ring nitrogen bridge not possible.

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