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  • 1
    Publication Date: 1992-07-01
    Print ISSN: 0304-3991
    Electronic ISSN: 1879-2723
    Topics: Electrical Engineering, Measurement and Control Technology , Natural Sciences in General , Physics
    Published by Elsevier
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  • 2
    Publication Date: 1992-03-01
    Print ISSN: 0044-2313
    Electronic ISSN: 1521-3749
    Topics: Chemistry and Pharmacology
    Published by Wiley
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  • 3
    Publication Date: 1993-04-01
    Print ISSN: 0044-2313
    Electronic ISSN: 1521-3749
    Topics: Chemistry and Pharmacology
    Published by Wiley
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  • 4
    Publication Date: 1994-07-01
    Print ISSN: 0044-2313
    Electronic ISSN: 1521-3749
    Topics: Chemistry and Pharmacology
    Published by Wiley
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Journal of materials science 13 (1994), S. 335-337 
    ISSN: 1573-4811
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 0044-2313
    Keywords: 1,3-Di-tert-butyl-2,2-dimethyl-4-X-4-Y-1,3,2,4-diazasilagermetidines (X, Y = halide, pseudohalide, alkyl or amino substituent) ; syntheses ; reduction ; 1H-NMR ; X-ray structure analyses ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cyclic Diazastannylenes. XXXII. On the Synthesis and Reactivity of Difunctional Cyclosilagermadiazanes - Formation of DigermanesThe cyclic bisaminostannylene Me2Si(t-BuN)2Sn 1 reacts with tetrahalides of germanium GeX4(X = Cl, Br, I) forming the bisaminodihalogengermanes 2a, 2b and 2c. The halogen atoms of the compounds 2 may be substituted by alkyl-, amino- and pseudohalide groups: Me2Si(t-BuN)2GeXY (X = Y = N3 3; X = Br, Y = Me 4, Y = t-Bu 6, Y = N(SiMe3)2 8a, Y = NEt2 9; X = Me, Y = N3 5a, Y = CN 5b; X = N3, Y = t-Bu 7, Y = N(SiMe3)2 10; X = I, Y = N(SiMe3)2 8b). Reduction of the compounds 2b and 4 with sodium naphthalide generates the digermanes (Me2Si(t-BuN)2GeR)2 (with R = Br 11, R = Me 12) Compound 8b crystallizes in the monoclinic space group P21/c with Z = 8 and lattice constants a = 16.205(8), b = 19.854(9), c = 17.537(9) Å, β = 107.50(9)°. Compound 11 crystallizes in the triclinic space group P1 with Z = 2 and lattice constants a = 8.921(4), b = 11.091(5), c = 17.590(8) Å, α = 80.5(1), β = 89.2(1), γ = 71.4(1)°.
    Notes: Das cyclische Bisaminotannylen Me2Si(t-BuN)2Sn 1 reagiert mit Germaniumtetrahalogeniden GeX4 (X = Cl Br, I) zu den Bisaminodihalogengermanen 2a, 2b und 2c. Die Halogenatome der Verbindungen 2 können durch Alkyl- und Amino- sowie Pseudohalogengruppen ersetzt werden: Me2Si(t-BuN)2GeXY (X = Y = N3) 3; X = Br, Y = Me 4, Y = t-Bu 6, Y = N(SiMe3)2 8a, Y = NEt2 9; X = Me, Y = N3 5a, Y = CN 5b; X = N3, Y = t-Bu 7, Y = N(SiMe3)2 10; X = I, Y = N(SiMe3)2 (8b). Durch Reduktion der Verbindungen 2b und 4 mit Natriumnaphthalid erhält man die Digermane (Me2Si(t-BuN)2GeR)2 (mit R = Br 11, R = Me 12). Die Verbindung 8b kristallisiert in der monoklinen Raumgruppe P21/c mit Z = 8 und a = 16,205(8), b = 19,854(9), c = 17,537(9) Å, β = 107,50(9)° und die Verbindung 11 kristallisiert in der triklinen Raumgruppe P1 mit Z = 2 und den Gitterkonstanten a = 8,921(4), b = 11,091(5), c = 17,590(8) Å, α = 80,5(1), β = 89,2(1), γ = 71,4(1)°.
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 125 (1992), S. 1375-1377 
    ISSN: 0009-2940
    Keywords: Silicon(IV) diazide ; Photolysis ; Matrix isolation ; Silylene, bis(amino)- ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Spectroscopic Identification of a Bis(amino)silyleneThe photolysis of the silicon diazide 3a in benzene solution and in an Ar matrix is described. Both irradiations cause the elimination of 3 equivalents of N2. Loss of N2 from 3a in benzene leads to the formation of the analytically investigated product or products 4 of uncertain structure. However, the matrix photolysis of 3a results in a compound which is stable up to 77 K and has been identified as the bis(amino)silylene 2d by comparison of its IR spectra with those of the homologous Sn and Ge compond.
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 619 (1993), S. 641-651 
    ISSN: 0044-2313
    Keywords: 1,3-Di-tert-butyl-2,2-dimethyl-4-azido-4-R- 1,3,2,4-diazasilagermaetidines (R = organic group, amine or azide); reactions with germylenes ; trapping of germa-imines ; insertion of Ge=N into C-H bonds ; NMR ; x-ray structure analyses ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reaction of a Cyclic Bis(amino)germylene with Germaniumazides: Trapping-Reactions of Unstable Germa-Imines.The cyclic bis(amino)germylene 1 reacts with different germaniumazides of the type Me2Si(NtBu)2Ge(R)N3 (R = Me (2), tBu (3), N(SiMe3)2 (4), R = N3 (5)). With the exception of 4 all azides lose dinitrogen when treated with 1 and the GeII center coordinates the α-nitrogen of the azide group. It seems to be reasonable to assume a transient germaimine (nitride) which is trapped by further reaction with the azide molecules 2 and 5 or by reaction with the solvent pyridine (3). In the case of 2 the germatetrazole [Me2Si(NtBu)2]GeN4[Ge(NtBu)2SiMe2]2 (6) is formed, the tetrazole nitrogens being exclusively substituted by germanium atoms (point symmetry of the molecule Cs(m)). When 1 is treated with 5 a tris(germa)amine [Me2Si(NtBu)2Ge(N3)]3N (8) is formed, which has an azide group attached to each Ge-atom. X-ray analysis reveals that the nine nitrogen atoms of the azide groups are coplanar with the trigonal planar Ge3N moiety (crystallographic symmetry: 3/m). The reaction of 1 with 3 is very surprising: the pyridine in the product Me2Si(NtBu)2Ge(C5H4N)—N(H)Ge(tBu)(NtBu)2SiMe2 (7) is bonded via an α-carbon atom while the remaining hydrogen has added to the nitride-nitrogen. 6 crystallizes in the monoclinic system space group C2/m, a = 24.306(9), b = 10.933(6), c = 19.420(9) Å, β = 91.81(2)° and Z = 4. 7 crystallizes in the hexagonal system space group P63/m with a = b = 16.73(1), c = 11.006(8) Å, γ = 120° and Z = 2, and 8 crystallizes in the monoclinic system space group P21/n, a = 11.341(6), b = 26.086(9), c = 13.244(7) Å, β = 98. I2(2)° mit Z = 4.
    Notes: Das cyclische Bis(amino)germylen 1 wurde mit verschiedenen Germaniumaziden Me2Si(NtBu)2GeR(N3) (R = Me (2), tBu (3), N(SiMe3)2 (4), N3 (5)) umgesetzt. Außer 4 reagieren alle Azide mit dem Germylen 1 unter Distickstoffentwicklung und gleichzeitigem Angriff des GeII-Zentrums auf den α-Stickstoff einer Azidgruppe. Das sich offenbar zwischenzeitlich bildende Germaimin (bzw. Germanitrid) wird durch weitere Reaktion mit der Azidkomponente (2 und 5) bzw. mit dem Lösungsmittel Pyridin abgefangen. Im Falle der Reaktion mit 2 bildet sich ein Germatetrazol [Me2Si(NtBu)2]GeN4[Ge(Me)(NtBu)2SiMe2]2 (6), dessen Stickstoffatome ausschließlich durch Germaniumatome substituiert sind (Punktsymmetrie Cs(m)). Bei der Reaktion mit 5 entsteht ein Tris(germa)amin [Me2Si(NtBu)2Ge(N3)]3N (7), das an jedem Germaniumatom noch jeweils eine Azidgruppe gebunden hat. Nach Röntgenstrukturanalyse befinden sich neben der trigonal planaren Ge3N-Einheit noch die 9 Stickstoffatome der Azidgruppen in der Molekülebene (kristallographische 3/m Symmetrie). Besonders überraschend ist die Reaktion von 1 mit 3 in Pyridin: im Produkt Me2Si(NtBu)2Ge(C5H4N)N(H)Ge(tBu)(NtBu)2SiMe2 (8) ist der Pyridinrest über das α-Kohlenstoffatom an das Germanium gebunden, während das verbleibende Wasserstoffatom sich an den Nitrid-Stickstoff addiert hat. 6 kristallisiert monoklin in C2/m mit a = 24,306(9), b = 10,933(6), c = 19,420(9) Å, β = 91,81(2)° mit Z = 4, 7 kristallisiert hexagonal in P63/m mit a = b = 16,73(1), c = 11,006(6) Å, γ = 120° mit Z = 2, und 8 kristallisiert monoklin in P21/n mit a = 11,341(6), b = 26,086(9), c = 13,244(7) Å, β = 98,12(2)° mit Z = 4.
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 1264-1270 
    ISSN: 0044-2313
    Keywords: 1,3-Di-tert-butyl-2,2-dimethyl-4,4-dichalcogen-1,3,2,4-diazasilagermetidines and -stannetidines ; digerma- and distanna- dichalcogencyclobutanes ; oxydation of germylenes and stannylenes by chalcogens ; reaction of a bis(amino)germylene with amine-N-oxide ; X-ray structure analyses ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Structures of Bis(amino)germa and -stanna ChalcogenidesThe cyclic bis(amino)germylene 1 and the -stannylene 2 react with elemental S, Se and Te to yield oxydation products of the general formula Me2Si(NtBu)2MEl2M(NtBu)2SiMe2 (M = Ge, El = S (4), El = Se (5), El = Te (6); M = Sn, El = Se (9), El = Te (10)). As may be deduced from X-ray structures (4, 5, 6, 9, 10) all compounds show similar central skeletons: the three spirocyclicly connected four-membered rings SiN2M (2x) and MEl2M are oriented in an orthogonal way to oneanother. The germanium and the tin atoms thus are in a distorted tetrahedral coordination while the chalcogen atoms only have two neighbours in acute angles. If 1 is allowed to react with trimethylamine-N-oxide, the oxygen is transferred to germanium and [Me2Si(NtBu)2GeO]3 (3) is formed. Contrarily to the other compounds 3 can be described as a trimer. There is a central almost planar Ge3O3 six-membered ring, the germanium atoms serving as spiro-cyclic centres to three GeN2Si four-membered rings (X-ray structure of 3). In the central four-membered rings of 4, 5, 6, 9 and 10 no transanular bonding between the chalcogen atoms have to be considered although these atoms have small distances to oneanother. The mean M-El distances have been found to be: Ge—O 1.762(5), Ge—S 2.226(3), Ge—Se 2.363(3), Ge—Te 2.592(5), Sn—Se 2.536(3), Sn—Te 2.741(3) Å.
    Notes: Das cyclische Bis(amino)germylen 1 sowie das -stannylen 2 reagieren mit elementarem S, Se oder Te zu Oxidationsprodukten der allgemeinen Formel Me2Si(NtBu)2MEl2M(NtBu)2SiMe2 (M = Ge, El = S (4), El = Se (5), El = Te (6); M = Sn, El = Se (9), El = Te (10)). Nach Röntgenstrukturanalysen (4, 5, 6, 9, 10) bestehen alle Verbindungen aus drei spirocyclisch verbundenen Vierringen SiN2M (2x) und MEl2M, die weitgehend orthogonal zueinander stehen. Die Germanium- und Zinnatome sind folglich verzerrt tetraedrisch koordiniert, während die Chalkogenatome jeweils zwei Nachbaratome unter spitzem Winkel besitzen. Setzt man 1 mit Trimethylamin-N-oxid um, so wird der Sauerstoff an das Germanium übergeben unter Bildung von [Me2Si(NtBu)2GeO]3 (3). Im Gegensatz zu den anderen Verbindungen kann 3 formal als Trimeres aufgefaßt werden: an einem zentralen weitgehend planaren Ge3O3-Sechsring sind spirocyclisch an den Germaniumatomen jeweils drei GeN2Si Vierringe geknüpft (Röntgenstrukturanalyse von 3). In den zentralen Vierringen von 4, 5, 6, 9 und 10 bestehen keine transanularen Wechselwirkungen zwischen den Chalkogenatomen, obwohl diese einen kurzen Abstand untereinander aufweisen. Die gemittelten M—El Abstände betragen: Ge—O 1,762(5), Ge—S 2,226(3), Ge—Se 2,363(3), Ge—Te 2,592(5), Sn—Se 2,536(3), Sn—Te 2,741(3) Å.
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