Synthese Und Kristallstrukturen Von Chlorometallaten [M = V(III), Mo(V)]

2001 ◽  
Vol 56 (8) ◽  
pp. 759-764 ◽  
Author(s):  
Soheila Chitsaz ◽  
Effat Iravani ◽  
Jochen Pauls ◽  
Bernhard Neumüller

[(THF)2LiCl2VCl2(THF)2] (1) and [Li(THF)4][OMoCl4(THF)] (2) can be prepared by the reactions of VCI3 with LiCl in THF and of Li(H)PtBu with OM0 CI4 in THF, respectively. 1 and 2 were characterized by IR spectroscopy, MS spectrometry (2) and X-ray crystallography. 1 can be obtained in two modifications depending on the temperature of crystallization. At -30 °C a triclinic form, 1a, was isolated from THF solution with one unique molecule per asymmetric unit. However, at 20 °C, 1b crystallized in the monoclinic space group P2/c. It possesses four independent molecules per asymmetric unit. According to the structure analyses 1 consists of a dinuclear complex with a planar LiCl2V four-membered ring while 2 consists of seperate ions [Li(THF)4]+ and [OMoCl4(THF)]-

IUCrData ◽  
2017 ◽  
Vol 2 (2) ◽  
Author(s):  
Mustapha Ait Elhad ◽  
Ahmed Benharref ◽  
Lahcen El Ammari ◽  
Mohamed Saadi ◽  
Abdelouahd Oukhrib ◽  
...  

The title compound, C16H23Cl2NO, crystallizes in the monoclinic space groupP21with two independent molecules (AandB) in the asymmetric unit. They have essentially the same conformation. Each molecule is built up from fused six- and seven-membered rings and an additional three-membered ring. The six-membered ring has an envelope conformation, with the C atom belonging to the three-membered ring forming the flap, while the seven-membered ring displays a boat conformation. In the crystal, molecules are linked into chains propagating along thea-axis direction by N—H...O hydrogen bonds.


2014 ◽  
Vol 69 (7) ◽  
pp. 799-803 ◽  
Author(s):  
Kiran Gupta ◽  
Peter Mayer ◽  
Ashutosh Pandey

1A[Al(OiPr)3]4 was reacted at ambient temperature with 3-chloropentanedione (3-ClacacH) in 1 : 1 molar ratio in toluene, to obtain the mono-substituted product. However, the bis-substituted dinuclear tetrakis(3-chloropentanedionato)-di-m-isopropoxy-dialuminum(III) [Al(μ-OiPr)(3-Clacac)2]2 () was isolated in 46% yield upon aging of the reaction mixture at −10 °C. The supernatant upon aging yielded a crop of tris-3-chloroacetylacetonate Al(3-Clacac)3·H2O (1) in 13% yield. Complexes 1A (monoclinic, space group P21/c with Z = 2) and 1(cubic, space group P43n with Z = 8) were characterized by elemental analyses, NMR and IR spectroscopy and single-crystal X-ray crystallography.


1995 ◽  
Vol 50 (7) ◽  
pp. 1018-1024 ◽  
Author(s):  
Axel Michalides ◽  
Dagmar Henschel ◽  
Armand Blaschette ◽  
Peter G. Jones

In a systematic search for supramolecular complexes involving all combinations of the cyclic polyethers 12-crown-4 (12C4), 15-crown-5 (15C 5), 18-crown-6 (18C 6) and dibenzo- 18-crown-6 (DB -18C6), and the geminal di- or trisulfones H2C(SO 2Me)2, H2C (SO2Et)2 and HC (SO2Me)3-n (SO2Et)n (n = 0 -3 ) , only the following four complexes could be isolated and unequivocally characterized by elemental analysis and 1H NMR spectroscopy: [(12C4){H2C (SO2Et)2}2] (3), [(18C6){H2C (S O2Me)2}] (4), [(DB -18C 6){H2C (SO2Et)2}] (5) and [(D B -18C 6)2{HC (SO2Me )(SO2Et)2}3] (6). The structure of 3 (triclinic, space group P1̄) consists of crystallographically centrosymmetric formula units, in which the disulfone molecules are bonded on each side of the ring by two C -H ··· O(crown) interactions originating from the central methylene group (H···O 213 pm) and from the methylene group of one EtSO2 moiety ( H ··· O 237 pm). Formula units related by translation are connected into parallel strands by a third type of reciprocal C -H ···O bond (H ···O 232 pm) between the second H atom of the central methylene group and a sulfonyl oxygen atom of the adjacent unit. The structure of 4 (monoclinic, space group C2/c) showed severe disorder of the crown ether and could not be refined satisfactorily. Compounds 5 and 6 crystallized as long and extremely thin fibres, indicative of linear-polymeric supramolecular structures; single crystals for X-ray crystallography were not available.


1975 ◽  
Vol 53 (23) ◽  
pp. 3596-3598 ◽  
Author(s):  
François Brisse ◽  
Aviva Battat ◽  
Jean-Claude Richer ◽  
Pierre Mazerolles ◽  
Alfreda Faucher

1,1-Dimethyl-1-germa (and-1-sila) -6,7-cycloundecanediol (C12H26O2Ge and C12H26O2Si) are isostructural as established by their X-ray powder patterns. The dimensions of the triclinic cells are as follows: for the silicon derivative, a = 10.53, b = 12.45, and c = 12.43 Å, α = 81.5°, β = 67.0°, and γ = 76.3°; for the germanium derivative, a = 10.56, b = 12.50, and c = 12.58 Å, α = 82.1°, β = 67.8°, and γ = 76.1°. If the space group is [Formula: see text] there will be two independent molecules in each asymmetric unit.


Author(s):  
Marcin Rojkiewicz ◽  
Piotr Kuś ◽  
Maria Książek ◽  
Joachim Kusz

Cathinones belong to a group of compounds of great interest in the new psychoactive substances (NPS) market. Constant changes to the chemical structure made by the producers of these compounds require a quick reaction from analytical laboratories in ascertaining their characteristics. In this article, three cathinone derivatives were characterized by X-ray crystallography. The investigated compounds were confirmed as: 1-[1-(4-methylphenyl)-1-oxohexan-2-yl]pyrrolidin-1-ium chloride (1, C17H26NO+·Cl−, the hydrochloride of 4-MPHP), 1-(4-methyl-1-oxo-1-phenylpentan-2-yl)pyrrolidin-1-ium chloride (2; C16H24NO+·Cl−, the hydrochloride of α-PiHP) and methyl[1-(4-methylphenyl)-1-oxopentan-2-yl]azanium chloride (3; C13H20NO+·Cl−, the hydrochloride of 4-MPD). All the salts crystallize in a monoclinic space group: 1 and 2 in P21/c, and 3 in P21/n. To the best of our knowledge, this study provides the first detailed and comprehensive crystallographic data on salts 1–3.


1983 ◽  
Vol 38 (3) ◽  
pp. 347-349 ◽  
Author(s):  
Herbert W. Roesky ◽  
Pierre Schäfer ◽  
Mathias Noltemeyer ◽  
George M. Sheldrick

Abstract The six membered ring of composition (CH3)2NCN3S2Cl2 3 a was prepared from N,N-dimethylguanidinhydrochloride and trithiadiazindichloride. 3 a was characterized on the basis of mass, 1H, 13C NMR spectra and X-ray structure analysis. Crystals of 3 a are monoclinic, space group P21/c, with a = 660.3(6), b = 834.5(7), c = 1774.7(15) pm, β = 112.83(6)° and Z = 4. The C2N unit lies approximately in the plane of the [-CNSNSN-] ring, with both Cl atoms on the same side of the ring.


2012 ◽  
Vol 68 (8) ◽  
pp. o2358-o2358 ◽  
Author(s):  
María-Guadalupe Hernández Linares ◽  
Gabriel Guerrero-Luna ◽  
Sylvain Bernès ◽  
Marcos Flores-Alamo ◽  
María A. Fernández-Herrera

Diosgenone [(20S,22R,25R)-spirost-4-en-3-one, C27H40O3] has been proposed as a new therapeutic alternative for the treatment of malaria. The first X-ray structure report for diosgenone was by Piroet al.[(2002).Z. Naturforsch. Teil C,57, 947–950] in the space groupP21(Z′ = 2). We now report a new polymorph in the same space group, with two molecules in the asymmetric unit. Both molecules have similar conformations, characterized by a skewed envelopeAring, which contains the C=C bond conjugated with the ketone functionality at C3. The dimorphism results from a modification of the relative orientation of the molecules in the asymmetric unit: two independent molecules were arranged antiparallel in the Piro report, while they are parallel in the present determination.


1999 ◽  
Vol 55 (3) ◽  
pp. 441-447 ◽  
Author(s):  
Lourdes Infantes ◽  
Concepción Foces-Foces ◽  
Jose Elguero

The crystal and molecular structures of 3(5),4-dimethylpyrazole, C5H8N2, (I), and of 3,4,5-trimethylpyrazole, C6H10N2, (II), have been determined at 200 K. In (I) the 4,5-dimethylpyrazole tautomer is present in the solid state and the six independent molecules in the asymmetric unit form trimers via NH...N hydrogen bonds related by a pseudo centre of symmetry. The asymmetric unit of (II) contains one and a half molecules: these exhibit NH proton disorder and are hydrogen bonded to each other via their respective NH groups to form chains. Ab initio calculations at HF and B3LYP/6-31G** levels indicate that the 3,4-dimethylpyrazole tautomer is more stable than the 4,5-dimethylpyrazole tautomer by only approximately 0.5  kcal  mol−1 (1 kcal mol−1 = 4.184 kJ mol−1).


1988 ◽  
Vol 43 (3) ◽  
pp. 323-327 ◽  
Author(s):  
H. Schumann ◽  
J. Loebel ◽  
D. van der Helm ◽  
M. B. Hossain

The title compound (1) is obtained as brownish crystals by reaction of HOCl3 with NaC5Me5 in tetrahydrofuran. The structure of 1, which has two slightly different independent molecules per asymmetric unit, has been elucidated by X-ray analysis. The crystals are triclinic with a = 1686.2(8) pm, b = 1816(1) pm, c = 846.5(4) pm, α = 92.02(7)°, β = 92.47(9)°, γ = 63.21(5)°, space group P1̄, D(calcd) = 1.560 g/cm3, and R = 0.0286, for 6219 observed reflections with I > 3σ(I).


1989 ◽  
Vol 67 (11) ◽  
pp. 1687-1692 ◽  
Author(s):  
James P. Johnson ◽  
Gregory K. MacLean ◽  
Jack Passmore ◽  
Peter S. White

The crystal structure of Te(N3)3SbF6 containing the first binary tellurium–nitrogen cation, triazidotellurium(IV) (Te(N3)3+), has been determined by X-ray crystallography. Single crystals of Te(N3)3SbF6 are monoclinic, space group P21/c with a = 9.201(6), b = 8.445(4), c = 13.582(7) Å, β = 100.36(5)°, Z = 4, final R1 = 0.036 for 1286 observed reflections. The structure consists of discrete Te(N3)3+ cations and distorted octahedral SbF6− anions, with some cation–anion interactions. The average Te—Nα—Nβ—Nγ bond distances in Te(N3)3+ are Te—Nα, 1.994(7); Nα—Nβ, 1.237(11); and Nβ—Nγ, 1.116(12) Å. The average bond angles about the Te, Nα, and Nβ atoms are 94.1(3)°, 116.5(6)°, and 173.7(9)°. Structural correlations with other TeX3+ species have yielded an estimate of the electronegativity of the N3− group to be 3.1 ± 0.1. Keywords: tetratellurium (2+) cation, triazidotellurium(IV) cation, electronegativity, azide.


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