Structure Types of Dihydroergotoxine Mesylates

2002 ◽  
Vol 67 (4) ◽  
pp. 490-501 ◽  
Author(s):  
Hana Petříčková ◽  
Jan Čejka ◽  
Michal Hušák ◽  
Bohumil Kratochvíl ◽  
Ivana Císařová ◽  
...  
Keyword(s):  
Single Crystal ◽  
Crystal Structures ◽  
Single Crystal Diffraction ◽  
X Ray ◽  
Ethanol Solvate

Three new crystal structures of dihydroergopeptines: dihydro-α-ergokryptine mesylate monohydrate acetone solvate (1), dihydro-α-ergokryptine mesylate monohydrate nitromethane solvate (2), and dihydroergocornine mesylate monohydrate methanol solvate (3) have been determined by X-ray single crystal diffraction. These structures were compared with published structures of dihydro-α-ergokryptine mesylate monohydrate ethanol solvate (4), dihydro-β-ergokryptine mesylate monohydrate methanol solvate (5), and dihydroergocristine mesylate monohydrate (6).

Preparation and Crystal Structures of Low-Valent Zirconocene Complexes Containing Tetramethyl(phenyl)cyclopentadienyl Ligands

2007 ◽  
Vol 72 (5-6) ◽  
pp. 679-696 ◽  
Author(s):  
Michal Horáček ◽  
Jiří Pinkas ◽  
Jiří Kubišta ◽  
Ivana Císařová ◽  
Róbert Gyepes ◽  
...  
Keyword(s):  
Single Crystal ◽  
Crystal Structures ◽  
Spectroscopic Methods ◽  
Single Crystal Diffraction ◽  
X Ray ◽  
Cyclopentadienyl Ligands ◽  
Low Valent

Zirconocene complex [ZrCl2(η5-C5Me4Ph)2] (1) prepared by metathesis of the appropriate lithium cyclopentadienide and ZrCl4 was reduced with magnesium in tetrahydrofuran in the presence of excess bis(trimethylsilyl)acetylene, yielding the low-valent complex [Zr(η5-C5Me4Ph)2- (η2-Me3SiC≡CSiMe3)] (2). However, in addition to 2, the reduction afforded an unexpected Zr(II) complex [Zr(η5-C5Me4Ph)2(s-trans-η4-buta-1,3-diene)] (3). Compounds 1-3 were characterized by spectroscopic methods and by X-ray single-crystal diffraction.

scholarly journals Structure of Biologically Active Benzoxazoles: Crystallography and DFT Studies

2021 ◽  
Vol 68 (1) ◽  
pp. 144-150
Author(s):  
Una Glamočlija ◽  
Selma Špirtović-Halilović ◽  
Mirsada Salihović ◽  
Iztok Turel ◽  
Jakob Kljun ◽  
...  
Keyword(s):  
Single Crystal ◽  
Crystal Structures ◽  
Energy Gap ◽  
Molecular Geometry ◽  
Biologically Active ◽  
Basis Set ◽  
Single Crystal Diffraction ◽  
X Ray ◽  
Experimental Values ◽  
Homo Lumo

Using X-ray single crystal diffraction, the crystal structures of biologically active benzoxazole derivatives were determined. DFT calculation was performed with standard 6-31G*(d), 6-31G** and 6-31+G* basis set to analyze the molecular geometry and compare with experimentally obtained X-ray crystal data of compounds. The calculated HOMO-LUMO energy gap in compound 2 (2-(2-hydroxynaphtalen-1-yl)-4-methyl-7-isopropyl-1,3-benzoxazol-5-ol) is 3.80 eV and this small gap value indicates that compound 2 is chemically more reactive compared to compounds 1 (4-methyl-2-phenyl-7-isopropyl-1,3-benzoxazol-5-ol) and 3 (2-(4-chlorophenyl)-4-methyl-7-isopropyl- 1,3-benzoxazol-5-ol). The crystal structures are stabilized by both intra- and intermolecular hydrogen bonds in which an intermolecular O–H⋅⋅⋅N hydrogen bond generates N3 and O7 chain motif in compounds 1, 2, and 3, respectively. The calculated bond lengths and bond angles of all three compounds are remarkably close to the experimental values obtained by X-ray single crystal diffraction.

Structure characterization with neutron powder data of LaGaO3 and NdGaO3 based on X-ray single-crystal data: evidence for an inversion center

1996 ◽  
Vol 211 (12) ◽  
Author(s):  
W. Marti ◽  
P. Fischer ◽  
J. Schefer ◽  
F. Kubel
Keyword(s):  
Single Crystal ◽  
Crystal Structures ◽  
Powder Diffraction ◽  
Neutron Powder Diffraction ◽  
Structure Characterization ◽  
Inversion Center ◽  
Crystal Data ◽  
Single Crystal Diffraction ◽  
X Ray

AbstractFrom neutron powder diffraction intensities it is often problematic to distinguish between centrosymmetry and non-centrosymmetry. X-ray single crystal diffraction may be more accurate. In this paper we compare refinement results of crystal structures on the basis of neutron powder data of orthorhombic NdGaO

Hydrogen bonding in hydroxypyridium salts

2018 ◽  
Vol 233 (7) ◽  
pp. 501-506
Author(s):  
Andrei V. Mironov ◽  
Victor A. Tafeenko ◽  
Dmitrii Yu. Grebenkin ◽  
Alexander E. Oblezov
Keyword(s):  
Hydrogen Bonding ◽  
Oxygen Atom ◽  
Single Crystal ◽  
Crystal Structures ◽  
Diffraction Data ◽  
Nitrate Anion ◽  
Single Crystal Diffraction ◽  
Space Group ◽  
X Ray ◽  
Unit Cells

Abstract The crystal structures of 6-methyl-2-ethyl-3-hydroxypyridiniun nitrate (C8H12NO)NO3 (I) and fumarate (C8H12NO)2C4H2O4 (II) were solved and refined from X-ray single crystal diffraction data (CuKα, (I) a=4.6477(2), b=14.5906(9), c=14.5551(8) Å, β=99.100(4)°, space group P21/c, Z=4, Rp/Rwp=0.033/0.047; (II) a=8.8293(3), b=13.4268(5), c=8.3893(3) Å, β=96.303(3)°, space group P21/c, Z=2, Rp/Rwp= 0.034/0.049). Both structures are built of infinite chains along ac diagonal of the unit cells formed by hydrogen bonding between the hydroxypyridium cation and the corresponding anion. Each fumarate anion is linked to four hydroxypyridium cations while nitrate anion is connected with two hydroxypyridium cations only leaving one oxygen atom in the nitrogen group isolated.

scholarly journals Environmentally Friendly Nafion-Catalyzed Synthesis of Substituted 2-Ethyl-3-Methylquinolines from Aniline and Propionaldehyde under Microwave Irradiation

Catalysts ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 877
Author(s):  
Chieh-Kai Chan ◽  
Chien-Yu Lai ◽  
Cheng-Chung Wang
Keyword(s):  
Reaction Mechanism ◽  
Microwave Irradiation ◽  
Single Crystal ◽  
Diffraction Analysis ◽  
Environmentally Friendly ◽  
Single Crystal Diffraction ◽  
X Ray ◽  
Related Data ◽  
Heating Source ◽  
Chemical Structures

Herein, we report a facile synthetic methodology for the preparation of 2,3-dialkylquinolines from anilines and propionaldehydes. This cyclization involved environmentally friendly Nafion® NR50 as an acidic catalyst with microwave irradiation as the heating source. A series of substituted 2-ethyl-3-methylquinolines were prepared from various anilines and propionaldehyde derivatives through this protocol with good to excellent yields. Some new chemical structures were confirmed by X-ray single-crystal diffraction analysis and the related data were provided. The plausible reaction mechanism studies are also discussed.

Crystal structures of (S)- and (R,S)-2,2′-bipyridine-3,3′-dicarboxylic acid 1,1′-dioxides and of their barium salts: absolute configuration and molecular distortion enforced by supramolecular self-assembly

1997 ◽  
Vol 212 (3) ◽  
Author(s):  
P. Vojtíšek ◽  
I. Císařová ◽  
J. Podlaha ◽  
Z. Žák ◽  
S. Böhm ◽  
...  
Keyword(s):  
Single Crystal ◽  
Dicarboxylic Acid ◽  
Crystal Structures ◽  
Absolute Configuration ◽  
Self Assembly ◽  
Barium Salt ◽  
X Ray Diffraction ◽  
X Ray

AbstractCrystal structures of the title compounds were determined by single crystal X-ray diffraction. Absolute configuration of the barium salt of (+)-(

Die Kristallstrukturen der isotypen Verbindungen Ba3[MoN4] und Ba3[WN4] / The Crystal Structures of the Isotypic Compounds Ba3[MoN4] and Ba3[WN4]

1991 ◽  
Vol 46 (5) ◽  
pp. 566-572 ◽  
Author(s):  
Axel Gudat ◽  
Peter Höhn ◽  
Rüdiger Kniep ◽  
Albrecht Rabenau
Keyword(s):  
Transition Metals ◽  
Single Crystal ◽  
Crystal Structures ◽  
Structure Type ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ternary Compounds ◽  
The Third

The isotypic ternary compounds Ba3[MoN4] and Ba3[WN4] were prepared by reaction of the transition metals with barium (Ba3N2, resp.) under nitrogen. The crystal structures were determined by single crystal X-ray diffraction: Ba3[MoN4] (Ba3[WN4]): Pbca; Z = 8; a = 1083.9(3) pm (1091.8(3) pm), b = 1030.3(3) pm (1037.5(3) pm), c = 1202.9(3) pm (1209.2(4) pm). The structures contain isolated tetrahedral anions [MN4]6- (M = Mo, W) which are arranged in form of slightly distorted hexagonal layers and which are stacked along [010] with the sequence (···AB···). Two of the three Ba atoms are situated between, the third one is placed within the layers of [MN4]-groups. In this way the structures can be derived from the Na3As structure type.

Comparative Structural Studies on Three-Coordinate Copper(I) Halide Complexes With Tertiary Phosphines. Crystal Structures of [(PPh2Mes)CuX]2 and [(PPhMes2)CuX]2 (Mes = Mesityl X = Cl, Br, I)

1992 ◽  
Vol 45 (7) ◽  
pp. 1155 ◽  
Author(s):  
GA Bowmaker ◽  
D Camp ◽  
RD Hart ◽  
PC Healy ◽  
BW Skelton ◽  
...  
Keyword(s):  
Single Crystal ◽  
Crystal Structures ◽  
Copper Atom ◽  
Structural Studies ◽  
Coordination Environment ◽  
X Ray ◽  
Tertiary Phosphines ◽  
Structure Determinations ◽  
Halide Complexes ◽  
The Subject

The 1 : 1 complexes of the substituted triphenylphosphine ligands mesityldiphenylphosphine and dimesitylphenylphosphine with copper(1) chloride, bromide and iodide have been the subject of single-crystal X-ray structure determinations at 295 K. All six complexes crystallize as air-stable dimeric molecules, [(PPh2Mes)CuX]2 and [ (PPhMes2)CUX]2 with each copper atom in a distorted trigonal PCuX2. coordination environment. Crystals of [(PPh2Mes)CuCl]2 (1) are monoclinic, P21/n, a 9.961(3), b 18.687(6), c 11.009(7) Ǻ, β 114.63(4)°; R was 0.049 for 2450 'observed' reflections. [(PPh2Mes)CuBrI2 (2) is monoclinic, P21/n, a 9.939(2), b 18.832(6), c 11.238(6) Ǻ, β 115.36(3)°; R was 0.046 for 1803 'observed' reflections. [(PPh2Mes)CuI]2.4/3 C6H6 (3) is rhornbohedral, R3, a 36.877(8), c 9.047(5) A; R was 0.039 for 2537 'observed' reflections. Crystals of [(PPhMes2)CuCl]2.2MeCN (4) are triclinic, Pi, a 15.783(7), b 9.570(4), c 8.914(4) Ǻ, α 72.43(3), β 76.37(3), γ 74.03(3)°; R was 0.045 for 3341 'observed' reflections. [(PPhMes2)CuBr]2.3C6H6 (5) is monoclinic, C2/c, a 9.694(6), b 30.15(2), c 20.66(2) Ǻ, β 98.00(7)°; R was 0.047 for 2117 'observed' reflections. [(PPhMes2)CuI]2.2MeCN (6) is orthorhombic, PP1nb, a 11.694(8), b 14.77(1), c 29.76(3) Ǻ; R was 0.049 for 3447 'observed' reflections. Cu-P bond lengths are: 2.196(2) A (1); 2.198(3) Ǻ (2); 2.222(5) and 2.226(5) Ǻ (3); 2.202(1) Ǻ (4); 2.197(3) A (5); 2.201(4) and 2.264(5) Ǻ (6). The geometries of the LCuX2 and CuX2Cu units are compared with data reported for other monomeric and dimeric compounds for both phosphorus- and nitrogen-based ligands L.

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