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  • 1
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Inorganic chemistry 30 (1991), S. 96-101 
    ISSN: 1520-510X
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1434-1948
    Keywords: Aluminium ; Amides ; Calcium ; Metallacycles ; Phosphorus ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Treatment of calcium bis[bis(trimethylsilyl)amide] with two equivalents of tris(trimethylsilylmethyl)alane yields (Me3SiCH2)2Al-N(SiMe3)2 (1) and the dimer [(Me3Si)2N-Ca(μ-CH2SiMe3)2Al(CH2SiMe3)2]2 (2). The five-coordinate bridging carbon atoms show Ca-C bond lengths of 264 and 268 pm. A similar reaction with calcium bis[bis(trimethylsilyl)phosphanide] gives the dimer [(Me3SiCH2)2Al-P(SiMe3)2]2 (3) with crystallographic C2 symmetry. A calcium-containing species is not isolable, however, in the presence of DME - ether cleavage reactions and the formation of the centrosymmetric dimer [(Me3SiCH2)2Al-OCH2CH2OMe]2 (4) are observed. The central moiety is an Al2O2 cycle with fivefold coordinated aluminium centers.
    Additional Material: 4 Ill.
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 1999 (1999), S. 2215-2220 
    ISSN: 1434-1948
    Keywords: Magnesium ; Metalation ; Phosphorus ; Polyhedra ; X-ray structures ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The magnesiation of triisopropylsilylphosphane with dibutylmagnesium in toluene yields the octanuclear complex [Mg8(PSiiPr3)6{P(H)SiiPr3}4] (1) which consists of MgPSiiPr3 units forming a hexagonal Mg6P6 prism, with two opposite Mg2P2 moieties capped by additional Mg[P(H)SiiPr3]2 groups. If a small amount of THF is present during the metalation reaction [(THF)4Mg6(PSiiPr3)6] (2) also containing a hexagonal Mg6P6 prism can be isolated. The magnesiation of H2P-SiiPr3 in tetrahydrofuran leads to the formation of the tetrameric complex [(THF)MgPSiiPr3]4(3) with a slightly distorted Mg4P4 cubane-like structure.The structures depend strongly on the steric strain caused by the trialkylsilyl substituents and the neutral coligands at the magnesium center. The highest steric strain, which is induced by coordination to every magnesium atom, leads to the smallest MgnPn polyhedron - the central Mg4P4 heterocubane moiety. In compounds 1 and 2 the hexagonal Mg6P6 prism is formed, however, with reduced steric strain as observed for 2 where the Mg-P bond lengths become more similar.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1434-1948
    Keywords: Bis(silyl)phosphanes ; Magnesium ; NMR spectroscopy ; Oligomers ; Phosphorus ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The metathesis reaction of (dme)LiPH2 and chlorodiisopropylsilane yields HP(SiHiPr2)2 (1) and P(SiHiPr2)3 (2). The metalation of 1 by n/sec-dibutylmagnesium in heptane leads to the formation of dimeric magnesium bis[bis(diisopropylsilyl)phosphanide] [(3)2]. A toluene solution of magnesium bis[bis(trimethylsilyl)phosphanide] (4) shows a dimer-trimer equilibrium in the 31P{1H}-NMR spectrum at -40°C with an increasing amount of the dimer with increasing temperature. A molecular mass determination by freezing-point depression in benzene yields a value of 516 g·mol-1, which lies between a monomeric and a dimeric molecule. Cooling of the toluene solution to -30°C leads to the precipitation of single crystals of monoclinic {(Me3Si)2P-Mg[μ-P(SiMe3)2]2}2Mg [(4)3].
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1434-1948
    Keywords: Cyclopentadienes ; Magnesium ; Metalations ; NMR spectroscopy ; Sandwich complexes ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of n/sec-dibutyl magnesium with 6-methyl-6-phenyl- and 6,6-dicyclopropylfulvene gives the β-hydride transfer products 1,1′-bis(1-phenylethyl)- and 1,1′-bis-(dicyclopropylmethyl)magnesocene, respectively. The latter crystallizes in the eclipsed conformation, whereas the first one shows an anti conformation in the solid state. Dimethyl-magnesium deprotonates 6-methyl-6-phenylfulvene with formation of 1,1′-bis(1-phenylethen-1-yl)magnesocene, which decomposes upon isolation. The deprotonation of 6,6-dicyclopropylfulvene with MgMe2 in thf solution yields [bis(tetrahydrofuran-O)][iro{cyclopropane-1,2′(1′-η5-cyclopentadienyl-1′,3′,3′-tricyclopropyl-1′,2′,3′,3a′-tetrahydropentalene)}-3a′-6′-η2-enyl]magnesium. In the absence of β-hydrogen atoms at the organometallic reagent as well as at the fulvene the addition reaction is the only possible reaction pathway. Thus, one Mg-C bond of MgMe2 adds to tetramethylfulvene to give quantitatively dimeric methylmagnesium ethyltetramethylcyclopentadienide. The bridging methyl groups are sterically shielded against further attack of the fulvene.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 1434-1948
    Keywords: Hydrogen bonds ; Indium ; Lithium ; Nitrogen heterocycles ; Zinc ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The lithiation of 2,5-di(tert-butyl)pyrrole (1) yields bis(tetrahydrofuran)lithium 2,5-di(tert-butyl)pyrrolide (2), which is monomeric in solution as well as in the solid state. Due to the coordination number of three for the lithium atom, short Li-O and Li-N bond lengths of 193 pm are observed. The metathesis reaction of 2 with tris(trimethylsilyl)-methylzinc chloride (3) gives colorless bis[tris(trimethyl-silyl)methylzinc] chloride 2,5-di(tert-butyl)pyrrolide (4). The pyrrolide ligand and the chlorine atom bridge the zinc atoms. One of the zinc atoms is bonded to the nitrogen atom of the pyrrolide substituent, while the other bonds to the opposite C-C bond. At 215 pm, the Zn-N bond is very long compared to those in alkylzinc amides, whereas the Zn-C distances lie in the range of Zn-C bond lengths found between zinc and η5-bonded cyclopentadienide ligands. The molecular structures of 1 and of the low-melting THF adduct 1·thf show a similar 2,5-di(tert-butyl)pyrrole molecule, but in the latter case a weak N-H···O bond is observed (N-H 97 pm, O···H 199 pm).
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 0044-8249
    Keywords: Kationen ; Phosphorheterocyclen ; Ylide ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 8
    ISSN: 0044-2313
    Keywords: Yttrium complexes ; yttrium tris[bis(trimethylsilyl)amide] ; yttrium tris[bis(trimethylsilyl)methanide] ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Bis(trimethylsilyl)amides and -methanides of Yttrium  -  Molecular Structures of Tris(diethylether-O)lithium-(μ-chloro)-tris[bis(trimethylsilyl)methyl]yttriate, solvent-free Yttrium Tris[bis(trimethylsilyl)amide] as well as the Bis(benzonitrile) ComplexThe reaction of yttrium(III) chloride with the three-fold molar amount of LiE(SiMe3)2 (E = N, CH) yields the corresponding yttrium derivatives. Yttrium tris-[bis(trimethylsilyl)amide] crystallizes in the space group P31c with a = 1 636,3(2), c = 849,3(2) pm, Z = 2. The yttrium atom is surrounded trigonal pyramidal by three nitrogen atoms with Y—N-bond lengths of 222 pm. Benzene molecules are incorporated parallel to the c-axes. The compound with E = CH crystallizes as a (Et2O)3LiCl-adduct in the monoclinic space group P21/n with a = 1 111,8(2), b = 1 865,2(6), c = 2 598,3(9) pm, β = 97,41(3)° and Z = 4. The reaction of yttrium tris[bis(trimethylsilyl)amide] with benzonitrile yields the bis(benzonitrile) complex, which crystallizes in the triclinic space group P1 with a = 1 173,7(2), b = 1 210,3(2), c = 1 912,4(3) pm, α = 94,37(1), β = 103,39(1), γ = 117,24(1)° and Z = 2. The amido ligands are in equatorial, the benzonitrile molecules in axial positions.
    Notes: Die Reaktion von Yttrium(III)-chlorid mit der dreifachen molaren Menge LiE(SiMe3)2 (E = N, CH) ergibt die entsprechenden Yttrium-Derivate. Yttrium-tris[bis(trimethylsilyl)amid] kristallisiert in der Raumgruppe P31c mit a = 1 636,3(2), c = 849,3(2) pm, Z = 2. Das Yttriumatom ist trigonal pyramidal koordiniert mit Y—N-Bindungslängen von 222 pm. Entlang der c-Achse sind Benzolmoleküle eingeschlossen. Die Verbindung mit E = CH kristallisiert als (Et2O)3LiCl-Addukt in der monoklinen Raumgruppe P21/n mit a = 1 111,8(2), b = 1 865,2(6), c = 2598,3(9) pm, β = 97,41(3)° und Z = 4. Die Umsetzung von Yttrium-tris[bis(trimethylsilyl)amid] mit Benzonitril ergibt einen Bis(benzonitril)-Komplex, der in der triklinen Raumgruppe P1 mit a = 1173,7(2), b = 1210,3(2), c = 1912,4(3) pm, α = 94,37(1), β = 103,39(1), γ = 117,24(1)° und Z = 2 kristallisiert. Die Amido-Liganden sind äquatorial, die Benzonitril-Moleküle axial koordiniert.
    Additional Material: 8 Ill.
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 621 (1995), S. 877-888 
    ISSN: 0044-2313
    Keywords: Barium ; Bis(trimethylsilyl)phosphanide ; Phosphanide ; Tin ; NMR ; X-ray Structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Characterization of Hetero-bimetallic Bis(trimethylsilyl)phosphanides of Barium and TinThe reaction of barium bis[bis(trimethylsilyl)amide] with one equivalent of bis(trimethylsilyl)phosphane in 1,2-dimethoxyethane (dme) yields the heteroleptic dimeric (dme)barium bis(trimethylsilyl)amide bis(trimethylsilyl)phosphanide. This colorless compound crystallizes in the monoclinic space group P21/n with a = 1 259.1(3), b = 1 822.7(4), c = 1 516.1(3) pm, β = 110.54(3)° and Z = 4. The central moiety of the centrosymmetric molecule is the planar Ba2P2-cycle with Ba—P-bond lengths of 329 and 334 pm. In the presence of bis[bis(trimethylsilyl)amino]stannylene hetero-bimetallic bis(trimethylsilyl)phosphanides of tin(II) and barium are isolated. If the reaction of Ba[N(SiMe3)2]2 and Sn[N(SiMe3)2]2 in the molar ratio of 1:2 with six equivalents of HP(SiMe3)2 is performed in toluene, barium bis{tin(II)-tris[bis(trimethylsilyl)phosphanide]} can be isolated. This compound crystallizes in the orthorhombic space group P212121 with a = 1 265.1(1), b = 2 290.1(3), c = 2 731.9(3) pm and Z = 4. The anions {Sn[P(SiMe3)2]3}- bind as two-dentate ligands to the barium atom which shows the extraordinary low coordination number of four. The addition of tetrahydrofuran (thf) to the above mentioned reaction solution leads to the elimination of tris(trimethylsilyl)phosphane and the formation of thf complexes of barium bis{tin(II)-bis(trimethylsilyl)phosphanide-trimethylsilylphosphandiide}. The derivative crystallizes from toluene in the monoclinic space group P21/c with a = 1 301.9(2), b = 2 316.3(3), c = 3 968.7(5) pm, β = 99.29(1)° and Z = 8.
    Notes: Bei der Reaktion von Barium-bis[bis(trimethylsilyl)amid] mit einem Äquivalent Bis(trimethylsilyl)phosphan in 1,2-Dimethoxyethan (DME) wird heteroleptisches, dimeres (1,2-Dimethoxyethan-O,O′)barium-bis(trimethylsilyl)-amid-bis(trimethylsilyl)phosphanid isoliert. Diese farblose Verbindung kristallisiert in der monoklinen Raumgruppe P21/n mit a = 1 259,1(3), b = 1 822,7(4), c = 1 516,1(3) pm, β = 110,54(3)° und Z = 4. Das zentrale Strukturelement des zentrosymmetrischen Moleküls ist der planare Ba2P2-Cyclus mit Ba—P-Bindungslängen von 329 und 334 pm. In Gegenwart des Bis[bis(trimethylsilyl)amino]stannylens erhält man heterobimetallische Bis(trimethylsilyl phosphanide von Zinn(II) und Barium. Wird die Umsetzung von Ba[N(SiMe32]2 and Sn[N(SiMe3)2]2 im molaren Verhältnis 1:2 mit sechs Äquivalenten HP(SiMe3)2 durchgeführt, kann Barium-bis{zinn(II)-tris-[bis(trimethylsilyl)phosphanid]} isoliert werden. Diese Verbindung kristallisiert in der orthorhombischen Raumgruppe P212121 mit a = 1 265,1(1), b = 2 290,1(3), c = 2 731,9(3) pm und Z = 4. Die Anionen {Sn[P(SiMe3)2])3}- binden als zweizähnige Liganden an das Bariumatom, das dadurch die ungewöhnlich niedrige Koordinationszahl vier aufweist. Die Zugabe von THF zu der oben beschriebenen Reaktionslösung führt zur Eliminierung von Tris(trimethylsilyl)phosphan und der Bildung von Barium-bis{zinn(II)-bis(trimethylsilyl)phosphanid-trimethylsilylphosphandiid). Das Derivat kristallisiert aus Toluol in der monoklinen Raumgruppe P21/c mit a = 1 301,9(2), b = 2 316,3(3), c = 3 968,7(5) pm, β = 99,29(1)° und Z = 8.
    Additional Material: 5 Ill.
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  • 10
    ISSN: 0044-2313
    Keywords: 3-oxo-3,4-dihydro-1λ5-phosphete-2-yl ; 3-oxo-2,3-dihydro-1λ5-phosphete-2-yl ; nmr ; ir ; mass spectra ; X-ray structures ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions of λ5-Diphosphetes with COS and CO2. Dihydro-λ5-Phosphetes1,1,3,3-Tetrakis(dimethylamino)-1λ5,3λ5-diphosphete, 1, reacts with COS to yield the (3-oxo-3,4-dihydro-1λ5-phosphete-2-yl)-phosphonothioic bis(dimethylamide) 7. Reaction of dimethyl substituted 1, i.e. 1,1,3,3-tetrakis(dimethylamino)-2,4-dimethyl-1λ5,3λ5-diphosphete 4, with COS and CO2 results in (3-oxo-2,3-dihydro-1λ5-phosphete-2-yl)-phosphonothioic bis(dimethylamide) 9, and (3-oxo-2,3-dihydro-1λ5-phosphete-2-yl)-phosphonic bis(dimethylamide) 10, respectively. Reaction mechanisms are suggested. 7, 9 and 10 are characterized by their properties, and their nmr, mass-, and ir-spectra. The results of X-ray structural analyses of 9 and 10 are reported and discussed.
    Notes: 1,1,3,3-Tetrakis(dimethylamino)-1λ5, 3λ5-diphosphet, 1, reagiert mit COS zu (3-Oxo-3,4-dihydro-1λ5-phosphet-2-yl)-phosphonothiosäure-bis(dimethylamid) 7. Die Umsetzung von dimethylsubstituiertem 1, d. h. 1,1,3,3-Tetrakis(dimethylamino)-2,4-dimethyl-1λ5,3λ5-diphosphet 4 mit COS und CO2 führt zu (3-Oxo-2,3-dihydro-1λ5-phosphet-2-yl)-phosphonothiosäure-bis(dimehthylamid) 9 bzw. (3-Oxo-2,3-dihydro-1λ5-phosphet-2-yl)-phosphonsäure-bis(dimethylamid) 10. Es werden Reaktionsmechanismen vorgeschlagen. 7, 9 und 10 sind durch Eigenschaften und ihre NMR-, Massen- und IR-Spektren charakterisiert. Die Ergebnisse der Röntgenstrukturanalysen von 9 und 10 werden mitgeteilt und diskutiert.
    Additional Material: 2 Ill.
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