Crystal and molecular structure of two C-phenyl pentitol derivatives

1978 ◽  
Vol 56 (23) ◽  
pp. 2915-2921 ◽  
Author(s):  
Douglas C. Rohrer ◽  
Jean-Claude Fischer ◽  
Derek Horton ◽  
Wolfgang Weckerle
Keyword(s):  
Molecular Structure ◽  
Crystal And Molecular Structure ◽  
Direct Methods ◽  
Coupling Constants ◽  
Monoclinic Space Group ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
Cell Dimensions ◽  
Palladium Catalyzed ◽  
Discrepancy Index

Grignard addition of phenylmagnesium bromide to 3,5-O-benzylidene-1-deoxy-D-erythro-2-pentulose (1) affords C-phenyl branched-chain pentitols having exclusively either the D-arabino (2) or D-ribo (5) stereochemistry according to the mode of substitution of 1. In order to determine the chirality of these products conclusively, the crystal and molecular structure of the unsubstituted pentitol 6 (from 2) has been determined. Crystals of 1-deoxy-2-C-phenyl-D-arabinitol (6; C11H16O4) are orthorhombic, space group P212121, with cell dimensions a = 8.9420(6), b = 18.910(1), c = 6.4263(6) Å, and Z = 4. The structure was solved by multi-solution direct methods and refined to a final discrepancy index of 5.6%. The molecule has an extended, planar zigzag conformation with the phenyl ring nearly perpendicular to this plane. Compound 6 forms one intramolecular (between 2-OH and O-4) and three intermolecular hydrogen bonds. Palladium-catalyzed hydrogenolysis of the 2-phenylcarbamate of 2 results in deoxygenation of the benzylic center with complete-inversion of configuration, as established by crystal-structure determination of the product 7. Crystals of 2(S)-4-O-acetyl-3,5-O-benzylidene-1,2-dideoxy-2-C-phenyl-D-erytro-pentitol (7; C20H22O4) are monoclinic, space group C2, with cell dimensions a = 19.102(1), b = 6.1925(5), c = 16.098(1) Å, β = 108.325(9)°, and Z = 4. The structure was solved by multi-solution direct methods and refined to a final discrepancy index of 5.9%. The molecule has an almost ideal planar, zigzag backbone conformation which incorporates the 1,3-dioxane ring. Comparison of the conformation observed in the crystal with that calculated from proton–proton coupling constants shows good agreement

The reaction of tetrasulphur dinitride with norbornadiene; the crystal and molecular structure of S4N2•C7H8, an eight-membered C2S4N2 heterocycle

1983 ◽  
Vol 61 (6) ◽  
pp. 1185-1188 ◽  
Author(s):  
Hans Koenig ◽  
Richard T. Oakley ◽  
A. Wallace Cordes ◽  
Mark C. Noble
Keyword(s):  
Molecular Structure ◽  
Least Squares ◽  
Dihedral Angle ◽  
Crystal And Molecular Structure ◽  
Direct Methods ◽  
Crystallographic Analysis ◽  
Monoclinic Space Group ◽  
Full Matrix ◽  
Space Group ◽  
X Ray

The reaction of tetrasulphur dinitride with norbornadiene produces the 1:1 adduct S4N2•C7H8; X-ray crystallographic analysis of this compound reveals that olefin addition cleaves one of the sulphur–sulphur bonds of S4N2, yielding a novel eight-membered C2S4N2 ring. Crystals of S4N2•C7H8 are monoclinic, space group P21/c, a = 6.127(1), b = 17.369(1), c = 9.580(1) Å, β = 106.74(1)°, V = 1003.8(5) Å3Z = 4. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.039. The S—S—N—S—N—S fragment of the C2S4N2 ring is planar to within 0.15 Å. The S—C—C—S unit is folded out of this plane to produce a dihedral angle of 74.5°.

Synthesis and conformational analysis of 2-arylseleno-1,3-dithianes. Crystal and molecular structure of 2-(4-methoxyphenylseleno)- and 2-(4-trifluoromethylphenylseleno)-1,3-dithiane

1986 ◽  
Vol 64 (4) ◽  
pp. 732-738 ◽  
Author(s):  
B. Mario Pinto ◽  
Jesus Sandoval-Ramirez ◽  
R. Dev Sharma ◽  
Anthony C. Willis ◽  
Frederick W. B. Einstein
Keyword(s):  
Molecular Structure ◽  
Nuclear Magnetic Resonance ◽  
Crystal And Molecular Structure ◽  
Chair Conformation ◽  
Axial Orientation ◽  
Monoclinic Space Group ◽  
Crystallographic Investigation ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
X Ray

The synthesis of 2-(4-methoxyphenylseleno)-1,3-dithiane 3 and 2-(4-trifluoromethylphenylseleno)-1,3-dithiane 5 from 2-chloro-1,3-dithiane 1 and the corresponding sodium arylselenolates is described. Nuclear magnetic resonance spectroscopic investigation of the products indicates that the compounds exist predominantly in a conformation in which the arylseleno moiety adopts an axial orientation. X-ray crystallographic investigation indicates that the 1,3-dithiane ring exists in the chair conformation with the arylseleno moiety in the axial orientation. Compound 3 is orthorhombic, space group P212121 with a = 5.449(2) Å, b = 9.217(2) Å, c = 24.860(3) Å, V = 1248.5 Å3, Z = 4. The structure was refined to R = 0.038 for 689 reflections with I > 2.3σ(I). Compound 5 is monoclinic, space group C2/c, with a = 28.628(7) Å, b = 5.246(2) Å, c = 21.342(5) Å, β = 121.12(1)°, V = 2743.8 Å3, Z = 8. Its structure refined to R = 0.064 for 966 reflections with I > 2.3σ(I).

Crystal and Molecular Structure Determination of N,N'-Diphenylacetamidinium Trifluoroacetate

1995 ◽  
Vol 60 (4) ◽  
pp. 576-582 ◽  
Author(s):  
Jan Ondráček ◽  
Svetlana Pakhomova ◽  
Bohumil Kratochvíl ◽  
Svatava Smrčková
Keyword(s):  
Molecular Structure ◽  
Lactate Dehydrogenase ◽  
Binding Site ◽  
Structure Determination ◽  
Crystal And Molecular Structure ◽  
Direct Methods ◽  
Monoclinic Space Group ◽  
Space Group

The structure of N,N'-diphenylacetamidinium trifluoroacetate - a model of the lactate dehydrogenase binding site - was solved by direct methods and anisotropically refined to R = 0.032 for 1 475 unique observed reflections. The compound crystallizes in the monoclinic space group P21/m, a = 5.942(1), b = 17.256(2), c = 7.817(1) Å, β = 103.05(1)°, V = 780.8(1) Å3, Z = 2, Dcalc = 1.38 g cm-3, μ(MoKα) = 0.11 mm-1, F(000) = 336.

Cyclische Diazastannylene, III1 Die Kristall-und Molekülstruktur der monoklinen Phase von 1.3-Di-tert-butyl-2.2-dimethyl-1.3.2.4λ2 -diazasilastannetidin / The Crystal and Molecular Structure of the Monoclinic Phase of 1,3-Di-feri-butyl-2,2-dimethyl-1,3,2,4λ2 -diazasilastannetidine

1978 ◽  
Vol 33 (1) ◽  
pp. 7-13 ◽  
Author(s):  
M. Veith
Keyword(s):  
Molecular Structure ◽  
Monoclinic Phase ◽  
Crystal And Molecular Structure ◽  
Three Dimensional ◽  
Monoclinic Space Group ◽  
Site Symmetry ◽  
Space Group ◽  
X Ray ◽  
Tert Butyl ◽  
Cell Dimensions

Abstract The crystal and molecular structure of the monoclinic phase of 1,3-di-tert-butyl-2,2-dimethyl-1,3,2,4λ2 -diazasilastannetidine has been determined from three-dimensional X-ray data collected on a two-circle diffractometer at -120 °C (MoKa radiation, 2623 reflexions, R - 0,050). The crystals are monoclinic, space group C2/c, with cell dimensions a = 10.655(5), b = 25.75(1), c = 17.33(1) Å, β = 106.8(1)° and Z = 12. Four monomeric (crystal site symmetry 2 (C2)) and four dimeric units (crystal site symmetry 1̄ (Ci)) are present in the structure interacting over tin-tin (3.68 Å). Remarkable are the very short Sn-N bond (2.09 Å) in the monomer and the donation bond Sn-N (2.39 Å) in the dimer. The coordination of the tin atoms in the different units is discussed in detail.

Crystal and Molecular Structure of N-(Trifluorosilyl)trimethylphosphinimine Dimer

1977 ◽  
Vol 32 (1) ◽  
pp. 22-25 ◽  
Author(s):  
W. S. Sheldrick ◽  
W. Wolfsberger
Keyword(s):  
Molecular Structure ◽  
Bond Length ◽  
Crystal And Molecular Structure ◽  
Direct Methods ◽  
Monoclinic Space Group ◽  
Space Group ◽  
Bond Lengths ◽  
Axial Ligands ◽  
Trigonal Bipyramidal ◽  
Pentacoordinate Silicon

N-(Trifluorosilyl)trimethylphosphinimine dimer crystallises in the monoclinic space group P21/n, Z = 2, with a= 6.314(2), b = 12.057(5), c = 10.936(4) Å, β = 95.45(2)°. The structure was solved by direct methods and refined to R 0.078 for 1117 independent reflections. The molecule is dimeric and centrosymmetric with an planar four-membered [SiN]2 ring containing trigonal-bipyramidal pentacoordinate silicon and trigonal nitrogen. Significant differences are observed in the bond lengths from silicon to its equatorial and axial ligands: Si-Neq 1.736(4), Si-Nax 1.857(4), Si-Feq1.606(4) and 1.607(3), Si-Fax 1.668(3) Å. The Si-Neq bond length is similar to that in tetracoordinate derivatives for which a (p →d) π bonding component has been postulated, while the Si-Nax distance is very much shorter than that observed in other pentacoordinate derivatives.

Crystal and Molecular Structure of the Copper(I)-thiolate-selenide Complex [Ph4P][Cu(SeS2CNC4H8)(S2CN2C4H8)] with an Unusual Se-S Bond

1999 ◽  
Vol 54 (10) ◽  
pp. 1313-1317 ◽  
Author(s):  
Qianfeng Zhang ◽  
Jinxi Chen ◽  
Maochun Hong ◽  
Xinquan Xin ◽  
Hoong-Kun Fun
Keyword(s):  
Molecular Structure ◽  
Bond Length ◽  
Crystal And Molecular Structure ◽  
Monoclinic Space Group ◽  
Space Group ◽  
A Cell

Reaction of a DMF solution of Cu(S2CNC4H8) with [Ph4P]2[WSe4] affords [Ph4P]2[WSe4- (CuS2CNC4H8)3] (1) and [Ph4P][Cu(SeS2CNC4H )(S2CN2C4H8)] (2) in which a Se atom from the decomposition of the WSe42- anion has reacted with the pyrrolidyldithiocarbamate (C4H8dtc) ligand anion to form the new ligand anion SeS2CNC4H8⊖. Complex 2 crystallizes with four formula units in the monoclinic space group P21/c in a cell of dimensions a = 10.5824(2), b = 18.7575(3), c = 18.3268(4) Å and ß = 109.0980(10)°. 6055 independent reflections above background were measured with a diffractometer and the structure was refined anisotropically to R =0.073. The anion contains a three-coordinated copper(I) atom. The C4H8dtc⊖ ligand is bonded to the Cu+ cation in a terminal fashion, while SeS2CNC4H8⊖ chelates the Cu+ cation. The Se-S bond length is 2.231 (4) Å.

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 di-o-anisylketone

1985 ◽  
Vol 63 (12) ◽  
pp. 3374-3377 ◽  
Author(s):  
C. Faerman ◽  
S. C. Nyburg ◽  
G. Punte ◽  
B. E. Rivero ◽  
A. A. Vitale ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Title Compound ◽  
Crystal And Molecular Structure ◽  
Monoclinic Space Group ◽  
Space Group ◽  
Compound C ◽  
Twist Conformation ◽  
Oxygen Atoms

The crystal and molecular structure of the title compound, C15H14O3, is described. Crystals are monoclinic, space group P21/n, a = 9.893(5), b = 10.719(5), c = 12.136(3) Å, β = 90.56(3)°. The molecule has a twist conformation and interactions between oxygen atoms of the methoxyl groups are thought to play some part in this.

Crystal and molecular structure of B,B-bis(p-tolyl)boroxazolidine and the orthorhombic form of B,B-diphenylboroxazolidine

1976 ◽  
Vol 54 (20) ◽  
pp. 3130-3141 ◽  
Author(s):  
Steven J. Rettig ◽  
James Trotter
Keyword(s):  
Molecular Structure ◽  
Statistical Analysis ◽  
Hydrogen Bonds ◽  
Crystal And Molecular Structure ◽  
Direct Methods ◽  
Length Variation ◽  
Full Matrix ◽  
Space Group ◽  
Phenyl Rings ◽  
Related Compounds

Crystals of B,B-bis(p-tolyl)boroxazolidine, 1c, are trigonal, a = 25.1028(9), c = 12.4184(7) Å, Z = 18, space group [Formula: see text]. And crystals of B,B-diphenylboroxazolidine, 1a, are orthorhombic, a = 17.6420(4), b = 14.2527(3), c = 10.205(1) Å, Z = 8, space group Pbca. Both structures were solved by direct methods and were refined by full-matrix least-squares procedures to final R values of 0.057 and 0.040 for 2230 and 1828 reflections with I ≥ 3σ(I) respectively. Both molecules have structures similar to related compounds and feature intermolecular N—H … O hydrogen bonds (N … O = 2.982(2) for 1c and 2.896(2) Å for 1a). Bond lengths are: for 1c; O—C, 1.413(3), O—B, 1.478(3), N—C, 1.488(3), N—B, 1.657(3), C(sp3)—C(sp3), 1.501(4), B—C, 1.616(3) and 1.623(3), mean C—C(ar), 1.395, N—H, 0.93(2) and 0.94(2), mean C(sp3)—H, 1.00, and mean C(ar)—H, 1.00 Å; for 1a; O—C, 1.409(2), O—B, 1.476(2), N—C, 1.489(2), N—B, 1.655(2), C(sp3)—C(sp3), 1.507(3), B—C, 1.613(2) and 1.620(2), mean C—C(ar), 1.391, N—H, 0.93(2) and 0.92(2), mean C(sp3)—H, 1.00, and mean C(ar)—H, 0.98 Å. A statistical analysis of the phenyl C—C distances in compounds 1a, 1b, and 1c has provided an example of statistically significant substituent-induced bond length variation in the phenyl rings.

The crystal structure of dibutyl-bis(pentamethylenedithiocarbamato)tin(IV)

1986 ◽  
Vol 51 (11) ◽  
pp. 2521-2527 ◽  
Author(s):  
Jan Lokaj ◽  
Eleonóra Kellö ◽  
Viktor Kettmann ◽  
Viktor Vrábel ◽  
Vladimír Rattay
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Least Squares ◽  
Coordination Polyhedron ◽  
Crystal And Molecular Structure ◽  
Distorted Octahedron ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray

The crystal and molecular structure of SnBu2(pmdtc)2 has been solved by X-ray diffraction methods and refined by a block-diagonal least-squares procedure to R = 0.083 for 895 observed reflections. Monoclinic, space group C2, a = 19.893(6), b = 7.773(8), c = 12.947(8) . 10-10 m, β = 129.07(5)°, Z = 2, C20H38N2S4Sn. Measured and calculated densities are Dm = 1.38(2), Dc = 1.36 Mg m-3. Sn atom, placed on the twofold axes, is coordinated with four S atoms in the distances Sn-S 2.966(6) and 2.476(3) . 10-10 m. Coordination polyhedron is a strongly distorted octahedron. Ligand S2CN is planar.

Sign in / Sign up

Export Citation Format

Share Document