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 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.

Crystal and Molecular Structure of Cycasin, (Z)-β-D-Glucopyranosyloxy-NNO-azoxymethane

1995 ◽  
Vol 48 (5) ◽  
pp. 1059 ◽  
Author(s):  
ME Tate ◽  
IM Delaere ◽  
GP Jones ◽  
ERT Tiekink
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Structure Analysis ◽  
Crystal And Molecular Structure ◽  
Crystal Structure Analysis ◽  
Monoclinic Space Group ◽  
Cell Dimensions ◽  
Cycas Revoluta ◽  
Unit Cell Dimensions

Characterization of cycasin , (Z)-β-D-glucopyranosyloxy-NNO-azoxymethane, from Cycas revoluta Thunb . is reported. A crystal structure analysis shows the azoxy substituents adopt a Z configuration. The colourless crystals are monoclinic, space group C2 with unit cell dimensions a 15.409(4), b 4.855(4), c 15.752(4) Ǻ, β 109.87(2)°, Z 4; the structure was refined to final R 0.033, 886 reflections with I ≥ 3.0σ(I) being used.

The synthesis, crystal and molecular structure of 1,1,3,3-tetramethylimidazolidinium diiodide methylene dichloride solvate, (C7H18N2)I2•CH2Cl2

1984 ◽  
Vol 62 (9) ◽  
pp. 1662-1665 ◽  
Author(s):  
Masood A. Khan ◽  
Clovis Peppe ◽  
Dennis G. Tuck
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Title Compound ◽  
Nmr Spectra ◽  
Crystal And Molecular Structure ◽  
Heavy Atom ◽  
Space Group ◽  
Simple Preparation ◽  
Methylene Dichloride ◽  
Heavy Atom Method

A simple preparation of the title compound, its crystal structure, and nmr spectra are reported. The compound crystallizes in the space group P21/n, with a = 8.109(2) Å, b = 16.183(4) Å, c = 11.968(4) Å, β = 93.45(2)°, V = 1567.7(7) Å−3, ρ = 1.987 g cm−3, Z = 4 (MoKα, λ = 0.71069 Å). The structure was solved by the heavy atom method and refined to the final R = 0.0415 for 1261 "observed" reflections. The structure consists of five-membered cyclic C7H18N22+ cations, iodide anions, and methylene dichloride molecules which are held loosely in the lattice.

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.

The Stereochemistry of Some Organic Derivatives of Group Vb Elements. Part X. The Crystal and Molecular Structure of Triphenylarsenic Difluoride

1975 ◽  
Vol 53 (11) ◽  
pp. 1647-1650 ◽  
Author(s):  
Ann Augustine ◽  
George Ferguson ◽  
Frank C. March
Keyword(s):  
Crystal And Molecular Structure ◽  
Heavy Atom ◽  
Three Dimensional ◽  
Arsenic Atom ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
Trigonal Bipyramidal ◽  
Phenyl Rings ◽  
Derivatives Of ◽  
Heavy Atom Method

The crystal structure of triphenylarsenic difluoride has been determined from three-dimensional X-ray diffractometer data. Crystals of Ph3AsF2 are orthorhombic, space group Pbcn, with four molecules of C18H15AsF2 in a unit cell of dimensions a = 6.270, b = 16.593, c = 14.519 Å; molecular symmetry C2 is required. The structure was solved by the heavy atom method and refined by full-matrix least-squares calculations to a final residual R of 0.054 for 979 intensities regarded as "observed" (I > 3σ(I)). The crystals contain well separated discrete molecules. The arsenic atom has near regular trigonal bipyramidal geometry with apical fluorine atoms (As—F 1.834(7) Å) and equatorial phenyl rings (mean As—C 1.925(5) Å). Idealized D3 symmetry is not achieved because of unequal rotations of the phenyl rings about the As—C bonds.

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 Triaqua-tri-μ-chloro-hexachloro-triangulo-trirhenium(III)-Bis[4,6-dimetylpyrimidine-2(1H)-thione hydrochloride]-Dihydrate

1987 ◽  
Vol 40 (12) ◽  
pp. 2123 ◽  
Author(s):  
LP Battaglia ◽  
AB Corradi ◽  
R Battistuzzi ◽  
T Manfredini
Keyword(s):  
Organic Molecules ◽  
Crystal And Molecular Structure ◽  
Heavy Atom ◽  
Chloride Ions ◽  
Water Molecules ◽  
Orthorhombic Space Group ◽  
Chlorine Atoms ◽  
Cell Dimensions ◽  
R Value ◽  
Heavy Atom Method

Reaction between rhenium(III) chloride and 4,6-dimethylpyrimidine-2(1H)- thione hydrochloride in concentrated HCl solution results in the formation of [Re3C19(H2O)3].2(C6H7N2S.HCl).-2H2O. The compound crystallizes in the orthorhombic space group Pnma with cell dimensions a 16.797(4), b 21.917(4), c 9.514(1) � and Z 4. The structure was solved by the heavy-atom method and refined by least-squares calculations to a final R value of 0.0517 (R' 0.0602). The structure consists of discrete [Re3Cl9(H2O)3] units, protonated organic molecules, chloride ions, and water molecules. In the cluster three rhenium atoms are linked to form a triangle, with chlorine atoms bridging each pair of rheniums which present short Re-Re bonds [2.440(1), 2.433(1) and 2.444(1) �]. Three water molecules in the equatorial plane and six chlorine atoms perpendicular to it (three above and three below) make the coordination around each rhenium distorted pentagonal bipyramidal.

Crystal and molecular structure of carbonylcyanide-4-chlorophenylhydrazone(4-chlorophenylhydrazonopropanedinitrile)

1984 ◽  
Vol 49 (10) ◽  
pp. 2363-2370
Author(s):  
Viktor Vrábel ◽  
Ernest Šturdík ◽  
Michal Dunaj-Jurčo ◽  
Jan Lokaj ◽  
Ján Garaj
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Structural Analysis ◽  
Least Squares Method ◽  
Crystal And Molecular Structure ◽  
Heavy Atom ◽  
Diffraction Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heavy Atom Method

The crystal structure of carbonylcyanide-4-chlorophenylhydrazone was solved by the single crystal X-ray diffraction method and interpreted by the heavy atom method. The compound crystallizes in the P21/c monoclinic group with 4 molecules per unit cell and with lattice parameters: a = 1.1843(3), b = 0.5944(1), c = 1.4922(3) nm and β = 117.92(2)°. The structure was refined by the least squares method for 1 078 observed reflections to a final value of R = 4.9%. The crystal structure consists of monomeric units, where hydrogen bonds were observed between atoms N3...H5 0.2193 nm and N3...H3 0.2404 nm between two molecules transformable through centre of symmetry -x, -y, -z. The name 4-chlorophenylhydrazonopropanedinitrile is recommended for the studied compound on the basis of this X-ray structural analysis.

Sign in / Sign up

Export Citation Format

Share Document