Cyclisierung von Amidoximen mit Oxybis(diphenylboran) / Cyclization of Amidoximes with Oxybis(diphenylborane)

1991 ◽  
Vol 46 (9) ◽  
pp. 1219-1222 ◽  
Author(s):  
Hans Möhrle ◽  
Karin Bluhme-Hensen ◽  
Birgit Middelhauve ◽  
Dietrich Mootz ◽  
Hartmut Wunderlich
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Structure Analysis ◽  
Heterocyclic Ring ◽  
Crystal Structure Analysis ◽  
Monoclinic Space Group ◽  
Space Group ◽  
Bifurcated Hydrogen Bond ◽  
Boron Heterocycles

Substituted amidoximes when reacted with oxybis(diphenylborane) do not yield ester chelates as main products but boron heterocycles. The compound obtained from p-toluamidoxime was found by crystal structure analysis to be 2-phenyl-4-(4-methylphenyl)-2,3-dihydro-1,3,5,2-oxadiazaborol (9). The conformation of the molecule is determined by angles of 29.1 and 24.4° between the planes of adjacent rings. Except N–O all bonds in the heterocyclic ring contain significant π character. Molecules are linked to chains by a weak bifurcated hydrogen bond. 9 crystallizes with the monoclinic space group P21/c, Ζ = 4, a = 5.574(2), b = 18.274(4), c = 12.754(4) Å, β = 106.41(2)°. Refinement of 227 parameters using 1709 observed reflections converged at R = 0.037.

Primäre und sekundäre Ethyl-und i-Propylsulfoniumsalze sowie Kristallstruktur von i-C3H7SH2+SbF6- [1]

1996 ◽  
Vol 51 (2) ◽  
pp. 277-285
Author(s):  
Rolf Minkwitz ◽  
Ulrike Lohmann ◽  
Hans Preut
Keyword(s):  
Crystal Structure ◽  
Structure Analysis ◽  
Bond Distance ◽  
Crystal Structure Analysis ◽  
Unit Cell ◽  
Monoclinic Space Group ◽  
Spectroscopic Methods ◽  
Sulfonium Salt ◽  
Space Group

Abstract The synthesis of salts of the type RnSH3-n+MF6- (R = C2H5, i-C3H7; n = 1, 2; M = As, Sb) by protonation of the corresponding thiols and sulfides in the superacid systems HF/MF5 is reported. The salts have been characterized by vibrational and NMR spectroscopic methods. Isopropylsulfonium hexafluoroantimonate is the first known example of a sulfonium salt, for which a SH bond distance has been determined by a crystal structure analysis, i-C3H7SH2+SbF6- crystallizes in the monoclinic space group P21/m with a = 568.0(4), b = 801.1(6), c = 1019.7(8) pm, β = 82.63(6) °, with two formula units per unit cell.

Darstellung und Charakterisierung der Carbosilazane Bis[tris(methylamino)silyl]methan und Bis[tris(phenylamino)silyl]methan/Preparation and Characterization of the Carbosilazanes Bis[tris(methylamino)silyl]methane and B is[tris(phenylamino)silyl]m ethane

1997 ◽  
Vol 52 (6) ◽  
pp. 707-710
Author(s):  
M. Jansen ◽  
S. Bzik
Keyword(s):  
Crystal Structure ◽  
Structure Analysis ◽  
Crystal Structure Analysis ◽  
Unit Cell ◽  
Monoclinic Space Group ◽  
Unit Cell Parameters ◽  
Space Group ◽  
Cell Parameters

Bis[tris(methylamino)silyl]methane (1) and bis[tris(phenylamino)silyl]methane (2) have been synthesized as potential precursors of porous oxygen-free solids by the reaction of bis(trichlorsilyl)methane with methylamine and with lithiated aniline, respectively. Compound 2 was characterized by a crystal structure analysis. It crystallizes in the monoclinic space group P 21 ,/c with the unit cell parameters a= 10.963(2),b= 17.801(2), c = 17.557(2) Å, β = 97.96(2)° and Z = 4 (R1, = 4,4 %, wR2 = 9,8 %, 5950 independent reflections).

Kristallstruktur und Konstitution des Perchlorbenzocyclobutens (β-C8Cl8)

1974 ◽  
Vol 29 (5) ◽  
pp. 831
Author(s):  
J. Haase ◽  
P. Widmann
Keyword(s):  
Crystal Structure ◽  
Structure Analysis ◽  
Crystal Structure Analysis ◽  
Spectroscopic Measurements ◽  
Space Group

Abstract The crystal structure of perchlorobenzocyclobutene (β-C8Cl8) has been investigated and solved by means of the unusual Patterson projection along the axis of twinning, by which the space group had been determined. As a result of the crystal structure analysis the constitution of the molecule, derived by J. Brandmüller and E. Ziegler from spectroscopic measurements, has been found to be true.

Regioselective N-Acetylation of 4-(2-Hydroxyphenyl)-2-phenyl-2,3- dihydro-1H-1,5-benzodiazepine Using Protection by an Intramolecular Hydrogen Bond

2009 ◽  
Vol 64 (8) ◽  
pp. 969-972 ◽  
Author(s):  
Carlos A. Escobar ◽  
Jorge Orellana-Vera ◽  
Andrés Vega ◽  
Dieter Sicker ◽  
Joachim Sieler
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Acetic Anhydride ◽  
Ambient Temperature ◽  
Intramolecular Hydrogen Bond ◽  
Structure Analysis ◽  
Crystal Structure Analysis ◽  
Hydroxyl Groups ◽  
Acetyl Group ◽  
Intramolecular Hydrogen

Since the amino and the hydroxyl groups of 4-(2-hydroxyphenyl)-2-phenyl-2,3-dihydro-1H-1,5- benzodiazepine can both act as nucleophiles, the introduction of both an N-acetyl and an O-acetyl group is expected when the compound is allowed to react with an excess of an electrophile such as acetic anhydride. An intramolecular hydrogen bond between OH and N-5 of the benzodiazepine has been used to obtain differentiation between the two possible sites of acetylation. Thus, this feature offers a preparatively utilizable protecting effect for the OH group and allows for a regioselective N-acetylation at ambient temperature. Both mono- and diacetylated compounds were prepared and characterized by crystal structure analysis

Re: Crystal Structures of Pyroaurite and Sjögrenite

1994 ◽  
Vol 38 ◽  
pp. 749-755 ◽  
Author(s):  
A. Olowe
Keyword(s):  
Crystal Structure ◽  
Crystal Structures ◽  
Structure Analysis ◽  
Crystal Structure Analysis ◽  
Metallic Ions ◽  
Chemical Formula ◽  
Metal Hydroxides ◽  
Space Group ◽  
Previous Discussion ◽  
Positively Charged

Abstract Pyroaurite and sjogrenite belong to the group of sandwiched lamellar metal hydroxides which have a fixed metallic ions MII:MIII ratio for a particular class. Their crystal structure consists of positively charged metal hydroxide blocks intercalated with negatively charged interlayers. The atomic positions for the interlayer are definite for a particular class. The exact chemical formula of the pyroaurite class is determined from crystal structure analysis to be MII 6MIII 2(OH)16-CO3-4.5H2O; it crystallizes in the space group Rm with a = 12.4376 Å and c = 23.4126 Å. Sjogrenite, MII 6 MIII 2(OH)16-CO3-4H2O crystallizes in the space group P63/mcm. The crystallogiraphy and structural relationship between these classes are discussed. Previous discussion on these compounds did not give any conclusion on the exact chemical formula and the atomic positions.

Über die Darstellung der (Chlorthio)sulfoniumsalze [(CH3)2SSSCl]+SbF6-, [(CH3)2SSCl]+SbF6- und des isomeren [(CH3)(Cl)S – SCH3]+SbCl6- / On the Preparation of the (Chlorothio)sulfonium Salts [(CH3)2SSSCl]+SbF6-, [(CH3)2SSCl]+SbF6- and the Isomer [(CH3)(Cl)S–SCH3]+SbCl6-

1990 ◽  
Vol 45 (12) ◽  
pp. 1637-1642 ◽  
Author(s):  
Rolf Minkwitz ◽  
Andreas Kornath ◽  
Renate Krause ◽  
Hans Preut
Keyword(s):  
Crystal Structure ◽  
Structure Analysis ◽  
Crystal Structure Analysis ◽  
Molar Ratio ◽  
Sulfonium Salts ◽  
Space Group

The preparation of the stable compounds [(CH3)2SSCl]+SbF6- and [(CH3)2,SSSCl]+SbF6- from [(CH3)2SH]+SbF6- and SCl2 and S2Cl2, resp., is reported.The isomer [(CH3)(Cl)S–SCH3]+SbCl6- is prepared from [SCl3]+SbCl6- and CH3SH in the molar ratio 1:2. For this salt a crystal structure analysis was carried out (Space group P212121, Z = 4, a = 750.1(4), b = 1133.7(3), c = 1614.8(3) pm).

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.

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.

scholarly journals Synthesis and Single Crystal X-Ray Structure of New (2E)-2-[3-(1H-Imidazol-1-yl)-1-phenylpropylidene]-N-phenylhydrazinecarboxamide

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Mohamed I. Attia ◽  
Hazem A. Ghabbour ◽  
Aida A. El-Azzouny ◽  
Omar A. Al-Deeb ◽  
Maha S. Almutairi ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Single Crystal ◽  
Title Compound ◽  
Spectroscopic Characterization ◽  
Monoclinic Space Group ◽  
Space Group ◽  
X Ray ◽  
Imine Bond

Synthesis, spectroscopic characterization and X-ray crystal structure of a new (2E)-2-[3-(1H-imidazol-1-yl)-1-phenylpropylidene]-N-phenylhydrazinecarboxamide (4) are reported. The stereochemistry of the title compound4, C19H19N5O, about the imine bond [1.296 (4) Å] was assigned to have (E)-configuration. In the urea moiety, the N–H entities aretransto each other, and one of these forms is an intramolecular N–H⋯H hydrogen bond. The compound crystallizes in the monoclinic space groupP21/cwitha= 5.8093 (2) Å,b= 20.5575 (6) Å,c= 14.0355 (5) Å,α= 90.00°,β= 97.365° (2),γ= 90.00°,V= 1662.36 (10) Å3, andZ= 4. The molecules are packed in crystal structure by weak intermolecular hydrogen interactions.

Unique 3D framework formed by adding MIIO4 groups into high Sb/P ratio phosphatoantimonates

2019 ◽  
Vol 234 (5) ◽  
pp. 301-306
Author(s):  
Wei-Long Zhang ◽  
Zhen-Gang Guo ◽  
Xiang-Feng Guan ◽  
Chinghwa Chen ◽  
Jiangang He ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Structure Analysis ◽  
Reflectance Spectrum ◽  
Crystal Structure Analysis ◽  
Band Gaps ◽  
Space Group ◽  
Optical Reflectance Spectrum ◽  
3D Framework ◽  
Single Crystal Structure Analysis

Abstract Explorations on a mixed metal phosphatoantimonate system led to the discovery of two new anhydrous phosphatoantimonates, namely, Cs4MSb6P4O28 (M=Mg, Zn), which represent the first examples of quinary AI – MII –SbV – PV– O systems. Single-crystal structure analysis reveals that the two title compounds crystallize in the tetragonal space group I41/a (No. 88). Their structures feature complicated 3D frameworks with interesting tunnel structures comprised of corner sharing MO4 tetrahedra, SbO6 octahedra and PO4 tetrahedra, with the Cs+ cations sitting in the tunnels to balance the valence. Optical reflectance spectrum measurements show that these two compounds are insulators with band gaps of about 4.5 eV.

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