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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3227-3240 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: λ5-Di- and -Triazaphospholines - Synthesis, Isomerization, and DecompositionThe reaction of amino[(trimethylsilyl)methylene]thioxophosphorane 1 with diazoalkanes leads to Δ1-diazaphospholines 3, 7, 11, and 12. These sensitive compounds are stabilized by 1,3-migration of a trimethylsilyl group, where 3 and 7 end in the Δ2-diazaphospholines 4 and 8 and 11 and 12 decompose by [1 + 4]cycloreversion to give the azines 14 and 15 as well as aminothioxophosphane intermediate 13. 13 could be trapped by reaction with diazoalkanes as aminomethylenethioxophosphoranes (18 and 19). The corresponding phosphane system 20 and 21 is available by reduction of 18 and 19, respectively, with triphenylphosphane. tert-Butyl azide (22) and 1 form triazaphospholine 23, which isomerizes thermally by silyl migration to give 24. Photochemically induced elimination of N2 leads to the λ5-azaphosphiridine 25; this system is also accessible by reaction of aminoiminothioxophosphorane 26 with diazomethane. In contrast, thermal reaction of trimethylsilyl azide (30) and 1 results in a λ5-thiaphosphirane 31. Compounds of this type (31, 32) can also be synthesized by [1 + 2]cycloaddition of sulfur and the corresponding iminomethylenephosphorane. - The X-ray structure analysis of the Δ2-diazaphospholine 5 is described, NMR data and decomposition of di- and triazaphospholines are discussed.
    Notes: Amino[(trimethylsilyl)methylen]thioxophosphoran 1 reagiert mit Diazoalkanen zu den Δ1-Diazaphospholenen 3, 7, 11 und 12. Diese stabilisieren sich unter 1,3-Trimethylsilyl-Verschiebung zu den Δ2-Diazaphospholenen 4 und 8 bzw. zerfallen unter [1 + 4]-Cycloreversion zu Azin (14 und 15) und dem Aminothioxophosphan 13. 13 konnte durch Reaktion mit Diazoalkan als Aminomethylenthioxophosphoran (18 und 19) abgefangen werden. Durch Entschwefelung von 18 bzw. 19 mittels Triphenylphosphan ist das entsprechende Phosphan-System 20 bzw. 21 zugänglich. tert-Butylazid (22) reagiert mit 1 zum Triazaphospholen 23, das thermisch unter Trimethylsilyl-Wanderung zu 24 isomerisiert und photochemisch unter N2-Eliminierung das λ5-Phosphiridin 25 liefert, ein Verbindungssystem, das ebenfalls durch Umsetzung eines Aminoiminothioxophosphorans (26) mit Diazomethan zugänglich ist. Bei der thermischen Reaktion von 1 und Trimethylsilylazid (30) wird hingegen das λ5-Thiaphosphiran 31 erhalten. Verbindungen dieses Typs (31, 32) sind auch durch Schwefelung der entsprechenden Iminomethylenphosphorane zugänglich. - Die Röntgenstrukturanalyse des durch partielle Hydrolyse von 4 erhaltenen Δ2-Diazaphospholens 5 wird angegeben, und die NMR-Daten sowie der Zerfall der Di- und Triazaphospholene werden diskutiert.
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 0009-2940
    Keywords: Cyclopentadienes, synthesis of ; [3 + 2] Cycloadditions of 1-metalla-1,3-dienes and alkynes ; 1-Metalla-1,3,5-trienes of tungsten, cyclization to cyclopentadiene complexes ; η1-Cyclopentadiene tungsten complexes ; Aminocarbene complexes of chromium and tungsten ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Organic Syntheses via Transition Metal Complexes, 54.  -  Cyclopentadienes from 1-Metalla-1,3-dienes and Alkynes by Cyclization of Intermediate 1-Metalla-1,3,5-trienes (Metal = Tungsten)We report on first examples of the formation of cyclopentadienes from a 1-metalla-1,3-diene LnM=C-C=C [LnM = W(CO)5] and an alkyne in [3 + 2] cycloaddition multistep reactions. In a first step the alkyne Et2N-C=C-Me (2) adds to the 1-metalla-1,3-diene (CO)5W = C(OEt)-CH=CHPh (1b) to give 1-metalla-1,3,5-trienes (CO)5W=C(NEt2)-CMe=C(OEt)-CH=CHPh (3b) and (CO)5W=C(OEt)-CH=C(NEt2)-CMe=CHPh (4b). In a second step 3b cyclizes to thecyclopentadiene complex 5, which has an η1 ylide-type structure as established by an X-ray analysis. Hydrolysis of 5 leads to the formation of a 3-aminocyclopentenone 7. The 1-metalla-1,3,5-triene 4b yields a cyclopentadiene complex 8. In contrast to 5 the carbon skeleton of 8 has a connectivity different from that of the C3 unit of the 1-metalla-1,3-diene 1.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: When the pyridinium salts (PyH)2[Me6Br12i]Cl6a (Me = Nb, Ta) are heated up to about 200°C an exothermic and irreversible transformation occurs. Thereby 6 Cla and 6 Bri exchange their positions. The observations can be interpreted in a way that the halogen sphere - in total or in part - is turned by an angle of 60° in respect to the Me6 octahedron.
    Notes: Die Pyridiniumsalze (PyH)2[Me6Br12i]Cl6a (Me = Nb, Ta) erfahren bei etwa 200°C eine exotherme und irreversible Umwandlung. Hierbei tauschen die 6 Cla-mit 6 Bri-Atomen die Plätze. Die vorliegenden Beobachtungen lassen sich so deuten. daß sich bei der Umwandlung die Halogensphäre (ganz oder in Teilbereichen) relativ zum Me6-Oktaeder um 60° dreht.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 524 (1985), S. 95-100 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 18C6 Crown Complex of Amidosulfuric AcidThe title compound (3) has been obtained from reaction of the crown ether 18C6 (1) with amidosulfuric acid (2) in water, methanol, and ethanol. The structure of the substance was elucidated with X-ray diffraction and IR data. The two constituents of 3 are connected through three oxygen-hydrogen bridges. 3 is ideally suited for the isolation and recovery of 1 from aqueous solutions.
    Notes: Durch Umsetzung des Kronenethers 18C6 (1) mit Amidoschwefelsäure (2) in Wasser, Methanol und Ethanol konnte die Titelverbindung (3) dargestellt werden. Die Struktur der Substanz wurde durch Röntgenstrukturanalyse und durch ihr IR-Spektrum aufgeklärt. Die beiden Komponenten von 3 sind durch drei Sauerstoff-Wasserstoff-Brücken miteinander verknüpft. 3 eignet sich hervorragend für die Isolierung und die Rückgewinnung von 1 aus wäßrigen Lösungen.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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