ChemInform Abstract: SYNTHESIS OF THE FIRST α-DIAZOPHOSPHINES. PHOSPHOROUS-CARBON MULTIPLE-BOND CHARACTER OF PHOSPHINOCARBENES

1985 ◽  
Vol 16 (47) ◽  
Author(s):  
A. BACEIREDO ◽  
G. BERTRAND ◽  
G. SICARD
Keyword(s):  
Multiple Bond ◽  
Bond Character

Multiple-bond character in Cp3U:CHPMe3: first low-temperature neutron diffraction analysis of a uranium organometallic complex

1990 ◽  
Vol 9 (3) ◽  
pp. 694-697 ◽  
Author(s):  
Raymond C. Stevens ◽  
Robert Bau ◽  
Roger E. Cramer ◽  
Dawood Afzal ◽  
John W. Gilje ◽  
...  
Keyword(s):  
Low Temperature ◽  
Neutron Diffraction ◽  
Diffraction Analysis ◽  
Multiple Bond ◽  
Organometallic Complex ◽  
Neutron Diffraction Analysis ◽  
Bond Character

Sr3Al2Ge4, Ca10Al6Ge9 und Ca20Al6Ge13. Neue Aluminium-Germanide / Sr3Al2Ge4, Ca10Al6Ge9 and Ca20Al6Ge13. New Aluminium Germanides

2007 ◽  
Vol 62 (8) ◽  
pp. 1071-1082 ◽  
Author(s):  
Marco Wendorff ◽  
Caroline Röhr
Keyword(s):  
Small Deviation ◽  
Multiple Bond ◽  
Ternary Systems ◽  
Monoclinic Space Group ◽  
Band Structure Calculation ◽  
Total Density ◽  
Space Group ◽  
The One ◽  
Total Density Of States ◽  
Bond Character

In the ternary systems Ca-Al-Ge and Sr-Al-Ge three germanides with new structure types have been synthesized from stoichiometric ratios of the elements. Their crystal structures were determined using single crystal X-ray data. In the structure of Sr3Al2Ge4 (monoclinic, space group C2/m, a = 1267.6(4), b = 416.2(2), c = 887.4(3) pm, β = 110.37(2)°, Z = 2, R1 = 0.0354) Al-Ge sheets with Al in tetrahedral (i. e. Al−) and Ge in threefold ψ-tetrahedral (i. e. Ge−) coordination against Ge are present. Thus, the compound can be classified as an electron precise Zintl phase. This finding is verified by the result of a band structure calculation (within the FP-LAPW approach), that shows a distinct minimum of the total density of states at the Fermi level. The structure of Ca10Al6Ge9 (trigonal, space group R3̅m, a = 1398.45(14), c = 2107.4(3) pm, Z = 6, R1 = 0.0613) contains complicated sheets of trigonal planar building units [AlGe3] and [AlGe4] tetrahedra. The compound Ca20[Al3Ge6]2[Ge] (hexagonal, space group P63/m, a = 1600.9(2), c = 458.48(7) pm, Z = 1, R1 = 0.0282) shows two planar trimers of [AlGe3] triangles of formula [Al3Ge6] besides isolated Ge atoms (i. e. Ge4−). The overall electron count of the latter compounds, that contain trigonal planar coordinated Al atoms and considerable multiple bond character of the Al-Ge bonds, shows a very small deviation from the Zintl concept, comparable to the one observed in other aluminium-germanides like SrAlGe.

Multiple-bond character between two carborane polyhedra: the two-electron reduction of biscarborane

1990 ◽  
Vol 112 (11) ◽  
pp. 4593-4594 ◽  
Author(s):  
Thomas D. Getman ◽  
Carolyn B. Knobler ◽  
M. Frederick Hawthorne
Keyword(s):  
Multiple Bond ◽  
Electron Reduction ◽  
Bond Character

Collision-Induced Dissociations of Negative-Ions Formed by Reaction of HO- With Alkyl and Aryl Silanes. The Formation of Multiple Bonds to Silicon

1988 ◽  
Vol 41 (1) ◽  
pp. 57 ◽  
Author(s):  
RA Ohair ◽  
JH Bowie ◽  
GJ Currie
Keyword(s):  
Proton Transfer ◽  
Ab Initio Calculations ◽  
Collisional Activation ◽  
Multiple Bond ◽  
Negative Ions ◽  
Transfer Reactions ◽  
Multiple Bonds ◽  
Common Features ◽  
Proton Transfer Reactions ◽  
Bond Character

Collisional activation of alkyl and aryl siloxide ions produces a variety of ions and neutrals containing double bonds to silicon. Sila enolate ions and sila acyl ions RSi =O are common features of the spectra of alkylsiloxide ions; ab initio calculations suggest these ions to have considerable multiple bond character. It is proposed that most reactions proceed through ion complex intermediates. Specific proton transfer reactions often occur for ions Me3SiCHR (R = C3H5, C3H3 or Ph), i.e. Me3SiCHR → -CH2(Me)2SiCH2R. In the particular case of the formation of PhCH2- from Me3SiCHPh, i.e. Me3SiCHPh → -CH2(Me)2SiCH2Ph → PhCH2- +Me2Si=CH2, the proton transfer competes with scrambling of all hydrogens in the decomposing ion.

[TcCl(CS)(dppe)2]·C6H6

2000 ◽  
Vol 57 (1) ◽  
pp. m23-m24 ◽  
Author(s):  
Jeffrey C. Bryan ◽  
Anthony K. Burrell ◽  
Gregory J. Kubas
Keyword(s):  
Title Compound ◽  
Multiple Bond ◽  
Benzene Solvate ◽  
Bond Character

The title compound, chlorobis[1,2-ethanediylbis(diphenylphosphine)-P,P′](thiocarbonyl-C)technetium benzene solvate, [TcCl(C46H42P4)(CS)]·C6H6, was obtained as one of two Tc-containing products isolated from the reaction between CS2and the electron-deficient complex [TcCl(dppe)2], where dppe is 1,2-ethanediylbis(diphenylphosphine). The structure exhibits an unusually short Tc—C distance [1.819 (6) Å], suggesting some multiple-bond character.

Reaktionen von Oxovanadium-Dipicolinatokomplexen mit Benzoylhydrazin. Die Kristallstrukturen von [VO(dipic)(NH2NHC(O)Ph) · NH2NHC(O)Ph · H2O, [C(NH2)3][VO(dipic)(NHNC(O)Ph)] · 2H2O und der „blauen“ Modifikation von [VO(dipic)(H2O)2] · 2H2O / Reactions of Oxovanadium(IV) and -(V) Dipicolinato Complexes with Benzoylhydrazine. Crystal Structures of [VO(dipic)(NH2NHC(O)Ph)] · NH2NHC(O)Ph · H2O · [C(NH2)3][VO(dipic)(NHNC(0)Ph)] · 2H 2O and the “Blue” Modification of [VO(dipic)(H2O) 2] · 2 H2O

1993 ◽  
Vol 48 (2) ◽  
pp. 125-132 ◽  
Author(s):  
Angelika Sundheim ◽  
Rainer Mattes
Keyword(s):  
Multiple Bond ◽  
Resonance Spectroscopy ◽  
Space Group ◽  
Bond Lengths ◽  
Spin Resonance ◽  
Pyridine Dicarboxylic Acid ◽  
In Trans ◽  
Carbonyl Bond ◽  
Axial Site ◽  
Bond Character

AbstractThe hydrazino complex [VO(dipic)(NH2NHC(O)Ph)] · NH2NHC(O)Ph · H2O (3) has been prepared by reaction of [VO(dipic)(H2O)] · 2H2O (1) with NH2NHC(O)Ph. (dipic = dianion of pyridine dicarboxylic acid). The hydrazido(2-) complex (guanid)[VO(dipic)(NHNC(O)Ph)] · 2H2O (4) was obtained by reaction of (guanid)[VO2(dipic)]·2H2O and NH2NHC(O)Ph. During the course of this reaction a terminally bonded oxygen atom is abstracted from the vanadium(V) center. 1, 3 and 4 have been characterized by X-ray single crystal diffraction, infrared, Raman and electron spin resonance spectroscopy.In 1 vanadium is six-coordinate, with the nitrogen atom of the dipic ligand in trans position to the oxo group. The two water molecules are also ligated in mutual trans positions. Vanadium is also six-coordinate in 3 and 4. In both, the dipic ligand is cis oriented with respect to the terminal oxo group. In 3 benzoylhydrazine, and in 4 the hydrazido(2 -) species NHNC(O)Ph act as N,O-chelate ligands, donating their NH2-, respectively NH-group to the remaining equatorial site and their CO-group to an axial site. The V - NH2(213.1(4) pm) and V - NH (190.5(2) pm) bond lengths differ considerably, indicating multiple bond character for the latter. In 3 the V -O(oxo) and V-O (carbonyl) bond lengths are 160.1(4) and 219.1(3) pm, and in 4 160.8(2) and 211.9(2) pm, respectively. Crystal data for 1: space group P 1̄, a = 656.2(2), b = 913.2(3), c - 1075.2(2) pm, α= 111.44(2), β = 100.16(2), γ = 94.81(3)°, Z = 2; 3: space group P1̄, a = 801.4(2), b = 1188.7(11), c = 1353.5(12) pm, α = 72.02(7), β = 88.31(7), γ = 70.60(7)°, Z = 2; 4: space group P 1̄, a = 1018.2(5), b = 1222.5(6), c = 1683.2(6) pm, α = 80.02, β = 89.95, γ = 78.73°, Z = 4.

Amido complexes of (cyclopentadienyl)dichlorotitanium(IV): titanium-nitrogen multiple-bond character. [Erratum to document cited in CA117(13):131316q]

1993 ◽  
Vol 32 (3) ◽  
pp. 368-368
Author(s):  
Dean M. Giolando ◽  
Kristin Kirschbaum ◽  
Lisa J. Graves ◽  
Urs Bolle
Keyword(s):  
Multiple Bond ◽  
Amido Complexes ◽  
Bond Character
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