Synthesis of [alkenyl(dimethylamino)carbene]tungsten complexes using the Peterson reaction. X-ray crystal structure of E-(CO)5W[C(NMe2)CH:CH(.eta.-C5H4)Fe(.eta.-C5H5)]

1989 ◽  
Vol 8 (5) ◽  
pp. 1275-1282 ◽  
Author(s):  
David W. Macomber ◽  
Puttannachetty. Madhukar ◽  
Robin D. Rogers
Keyword(s):  
Crystal Structure ◽  
X Ray ◽  
Tungsten Complexes

Eine effiziente Synthesemethode für DiarylallenyIiden(pentacarbonyl)chrom- und -wolfram-Komplexe -Kristallstruktur von (CO)5Cr=C=C=CPh2 / An efficient Synthesis of Diarylallenylidene Pentacarbonyl Chromium and Tungsten Complexes - Crystal Structure of (CO)5Cr=C=C=CPh2

1994 ◽  
Vol 49 (9) ◽  
pp. 1207-1214 ◽  
Author(s):  
Helmut Fischer ◽  
David Reindl ◽  
Gerhard Roth
Keyword(s):  
Crystal Structure ◽  
Structure Analysis ◽  
Good Yield ◽  
Efficient Synthesis ◽  
X Ray ◽  
Tungsten Complexes ◽  
And Tungsten

An efficient synthesis of diarylallenylidene pentacarbonyl chromium and tungsten com­plexes is presented. Irradiation of M(CO)6 in THF affords (CO)sM[THF], Substitution of the THF ligand by diarylpropargylalcoholate and subsequent desoxygenation with COCF gives the title compounds in good yield. (The structure of diphenylallenylidene pentacarbonyl chromium has been determined by X-ray structure analysis

Tungsten complexes with bridging alkylidyne ligands: X-ray crystal structure of [(η-Me6C6)(OC)2Cr(µ-CC6H4Me-4)W(CO)2(η-C5H5)]·CH2Cl2

1980 ◽  
pp. 948-949 ◽  
Author(s):  
Michael J. Chetcuti ◽  
Michael Green ◽  
John C. Jeffery ◽  
F. Gordon A. Stone ◽  
Audrey A. Wilson
Keyword(s):  
Crystal Structure ◽  
X Ray ◽  
Tungsten Complexes

Synthesis and reactions of cycloheptadienyl and cyclooctadienyl tungsten complexes: X-ray crystal structure of [W(CO)2(PPh3)2(η5-C7H9)][BF4]

2004 ◽  
Vol 689 (4) ◽  
pp. 848-859 ◽  
Author(s):  
Keith P Carruthers ◽  
Madeleine Helliwell ◽  
Jonathan R Hinchliffe ◽  
Ana-Lucia A.B deSouza ◽  
Dale M Spencer ◽  
...  
Keyword(s):  
Crystal Structure ◽  
X Ray ◽  
Tungsten Complexes

Synthesis, characterization, and fluxional behavior in solution of the salts Et4N+[Me2Ga(N2C5H7)(OCH2CH2X)]M(CO)3− (where N2C5H7 = 3,5-dimethylpyrazolyl, X = NMe2 or SEt, and M = Cr, Mo, or W). X-Ray crystal structure of the W complex with X = NMe2

1990 ◽  
Vol 68 (1) ◽  
pp. 109-114 ◽  
Author(s):  
Kenneth S. Chong ◽  
Steven J. Rettig ◽  
Alan Storr ◽  
James Trotter
Keyword(s):  
Crystal Structure ◽  
Variable Temperature ◽  
Heavy Atom ◽  
Carbonyl Groups ◽  
Nmr Studies ◽  
X Ray ◽  
H Nmr ◽  
Allyl Complex ◽  
Tungsten Complexes ◽  
Infrared Studies

The tricarbonyl anions of Cr, Mo, and W incorporating unsymmetrical tridentate chelating pyrazolyl gallate ligands, [Me2Ga(N2C5H7)(OCH2CH2X)]M(CO)3−, have been isolated as their crystalline Et4N+ salts. 1H nmr and solution infrared studies indicate that the octahedral anions display a facial arrangement of the gallate ligand and the three carbonyl groups. This stereochemistry has been proven definitively for the tungsten complex with X = NMe2 by an X-ray structure determination (see below). Fluxional behavior for the anions in d6-acetone solution has been demonstrated by variable temperature 1H nmr studies and is compared to similar behavior displayed by the neutral molybdenum "allyl" complex, [Me2Ga(N2C3H3)(OCH2CH2NMe2)]Mo(CO)2(η3-C4H7). Crystals of tetraethylammonium [dimethyl(3,5-dimethylpyrazol-1-yl)(2-N,N-dimethylaminoethoxy)gallato-N2,N3,O]tricarbonyltungstate are orthorhombic, a = 11.312(9), b = 33.111(9), c = 7.445(6) Å, Z = 4, space group P212121. The structure was solved by conventional heavy atom methods and was refined by full-matrix least-squares procedures to R = 0.033 and Rw = 0.034 for 2508 reflections with I ≥ 3σ(I). The [Me2Ga(N2C5H7)(OCH2CH2NMe2)]W(CO)3− anion has fac-octahedral coordination geometry with W—O = 2.228(7), W—N(pyrazolyl) = 2.299(8), W—N(amine) = 2.37(1), and W—CO = 1.91 (1)–1.92(1) Å. Keywords: pyrazolyl-gallate complexes, fluxional behavior of Ga–W complexes, crystal structure of Ga–W complex, gallate–tungsten complexes.

A study on α-RuCl3 crystal structure by scanning tunneling microscopy

1989 ◽  
Vol 47 ◽  
pp. 30-31
Author(s):  
H.-J. Cantow ◽  
H. Hillebrecht ◽  
S. Magonov ◽  
H. W. Rotter ◽  
G. Thiele
Keyword(s):  
Crystal Structure ◽  
Density Distribution ◽  
Scanning Tunneling Microscopy ◽  
Electron Density ◽  
Structure Determination ◽  
Electron Density Distribution ◽  
Scanning Tunneling ◽  
Monoclinic Space Group ◽  
Tunneling Microscopy ◽  
X Ray

From X-ray analysis, the conclusions are drawn from averaged molecular informations. Thus, limitations are caused when analyzing systems whose symmetry is reduced due to interatomic interactions. In contrast, scanning tunneling microscopy (STM) directly images atomic scale surface electron density distribution, with a resolution up to fractions of Angstrom units. The crucial point is the correlation between the electron density distribution and the localization of individual atoms, which is reasonable in many cases. Thus, the use of STM images for crystal structure determination may be permitted. We tried to apply RuCl3 - a layered material with semiconductive properties - for such STM studies. From the X-ray analysis it has been assumed that α-form of this compound crystallizes in the monoclinic space group C2/m (AICI3 type). The chlorine atoms form an almost undistorted cubic closed package while Ru occupies 2/3 of the octahedral holes in every second layer building up a plane hexagon net (graphite net). Idealizing the arrangement of the chlorines a hexagonal symmetry would be expected. X-ray structure determination of isotypic compounds e.g. IrBr3 leads only to averaged positions of the metal atoms as there exist extended stacking faults of the metal layers.

X-ray Crystal Structure of ?9-THC-tosylate

Planta Medica ◽  
2008 ◽  
Vol 74 (03) ◽  
Author(s):  
W Gul ◽  
P Carvalho ◽  
D Slade ◽  
M Avery ◽  
JR Duchek ◽  
...  
Keyword(s):  
Crystal Structure ◽  
X Ray
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