ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Organometallics 1 (1982), S. 756-757 
    ISSN: 1520-6041
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 115 (1982), S. 3243-3256 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Chiral SFeCoM Clusters: Enantiomer Separation and Determination of the Absolute ConfigurationThe racemates of the clusters SFeCoMCp(CO)8 (1, M = Cr, Mo, W) were converted by the optically active ligand (—)-(R)-PMePrPh (2) to the pairs of diastereomers SFeCoMCp(CO)7—PMePrPh (3, M = Cr, Mo, W). These could be separated by fractional crystallization. Their reconversion to the pure optically active clusters 1 was achieved by scavenging of the phosphane ligand by methyl iodide under CO pressure. The clusters show rather high [α]-values. The absolute configuration of the molybdenum and tungsten compounds was determined by X-ray analysis and correlation of the ORD spectra. The enantiomers are relatively stable against thermal, but not against photochemical racemization.
    Notes: Die Racemate der Cluster SFeCoMCp(CO)8 (1, M = Cr, Mo, W) wurden mit dem optisch aktiven Liganden (—)-(R)-PMePrPh (2) in die Diastereomerenpaare SFeCoMCp(CO)7—PMePrPh (3, M = Cr, Mo, W) übergeführt. Diese ließen sich durch fraktionierende Kristallisation trennen. Ihre Rückumwandlung in die reinen optisch aktiven Cluster 1 gelang durch Abfangen des Phosphan-Liganden mit Methyliodid unter CO-Druck. Die Cluster zeigen z. T. sehr hohe [α]-Werte. Die absolute Konfiguration der Molybdän- und Wolframverbindungen wurde durch Röntgenstrukturanalyse und Korrelation der ORD-Spektren bestimmt. Die Enantiomeren sind recht stabil gegen thermische, nicht jedoch gegen photochemische Racemisierung.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 117 (1984), S. 2429-2437 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Double Metal Exchange in the Clusters SFeCo2(CO)9 and SRuCo2(CO)9Single metal exchange in SFeCo2(CO)9 (1) and SRuCo2(CO)9 (2) had yielded the mixed metal clusters SFeCoMCp(CO)8 (3, M = Cr, Mo, W) and SRuCoMCp(CO)8 (4, M = Mo, W). For the iron containing clusters 3 the metal exchange by the Co-As elimination method could be applied once more: via the intermediates SFeCoMCp(CO)7 - AsMe2 - M′Ln (5 - 7, M′ = Cr, Mo, W, Mn, Fe) the clusters SFeMM′Cp2(CO)7 (10) were formed, however only for M, M′ = Mo, W. The ruthenium containing clusters 4 reacted by the direct method with [M′Cp(CO)3]2 (M = Mo, W) to form the clusters SRuMM′Cp2(CO)7 (11, M, M′ = Mo, W).
    Notes: Einfacher Metallaustausch hatte aus SFeCo2(CO)9 (1) und SRuCo2(CO)9 (2) die Hetero-Cluster SFeCoMCp(CO)8 (3, M = Cr, Mo, W) und SRuCoMCp(CO)8 (4, M = Mo, W) ergeben. Auf die eisenhaltigen Cluster 3 ließ sich der Metallaustausch nach der Co-As-Eliminierungs-Methode erneut anwenden: über die Zwischenstufen SFeCoMCp(CO)7 - AsMe2 - M′Ln (5 - 7, M′ = Cr, Mo, W, Mn, Fe) entstanden, allerdings nur für M, M′ = Mo, W, die Cluster SFeMM′Cp2(CO)7 (10). Die rutheniumhaltigen Cluster 4 reagierten nach der Direktmethode mit [M′Cp(CO)3]2 (M′ = Mo, W) zu den Clustern SRuMM′Cp2(CO)7 (11, M, M′ = Mo, W).
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 117 (1984), S. 2438-2451 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Basic Cluster Reactions: Opening and Partial Fragmentation of Tetranuclear Clusters by COThe influence of CO on 16 mixed tetranuclear clusters of the general type M4(μ3-E(μ2-AsMe2) with M = Co, Fe, Ru, Mo, W, and E = S, PR, CR is reported. In all cases fragmentation with formation of trinuclear clusters occurs at slightly elevated pressures, during which a Co - As unit is normally eliminated. At normal pressure intermediates are observed in 7 cases, 4 of which can be isolated. Crystal structure analysis of the intermediate FeCo2MoSAsMe2Cp(CO)10 (8a) has shown that two metal-metal bonds are opened upon addition of CO with formation of the new EM3(μ-AsM) cluster framework. Under vacuum the intermediates are reconverted to the starting clusters with elimination of CO.
    Notes: Bei der Einwirkung von CO auf 16 Hetero-Vierkerncluster des allgemeinen Typs M4(μ3-E)(μ2-AsMe2) mit M = Co, Fe, Ru, Mo, W und E = S, PR, CR tritt in allen Fällen unter geringem Überdruck Abbau zu Dreikernclustern ein, wobei in der Regel eine Co - As-Einheit abgespalten wird. Bei Normaldruck werden in 7 Fällen Zwischenstufen beobachtet, die in 4 Fällen auch isolierbar sind. Durch Kristallstrukturanalyse der Zwischenstufe FeCo2MoSAsMe2Cpt(CO)10 (8a) wird belegt, daß durch Addition von CO zwei Metall-Metall-Bindungen geöffnet werden, wodurch das neuartige EM3(μ-AsM)-Clustergerüst entsteht. Im Vakuum wandeln sich die Zwischenstufen unter Abspaltung von CO wieder in die Ausgangscluster zurück.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 115 (1982), S. 3224-3242 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Chiral SFeCoM Clusters: Synthesis, Side Reactions, and Proof of ChiralityFrom SFeCo2(CO)9 (1) via the intermediates SFeCo2(CO)8—AsMe2—MCp(CO)3 (3, M = Cr, Mo, W) by the Co—As elimination method the chiral clusters SFeCoMCp(CO)8 (8, M = Cr, Mo, W) could be obtained. From such reactions other clusters resulted too, of which one with a SCo2Mo(μ-AsMe2) framework (10b) and one with a SCo2W(μ-AsCoAs) framework (12) were identified by crystal structure analyses. The chirality of the intermediates 3 as well as that of PMe2Ph derivatives of the clusters 1, 8, and 10 could be proved NMR-spectroscopically by the diastereotopism of the AsMe2- and PMe2 methyl groups, respectively.
    Notes: Aus SFeCo2(CO)9 (1) ließen sich über die Zwischenstufen SFeCo2(CO)8—AsMe2—MCp(CO)3 (3, M = Cr, Mo, W) nach der Co—As-Eliminierungsmethode die chiralen Cluster SFeCoMCp(CO)8 (8, M = Cr, Mo, W) gewinnen. Bei solchen Reaktionen entstanden auch andere Cluster, von denen einer mit SCo2Mo(μ-AsMe2)-Gerüst (10b) und einer mit SCo2W(μ-AsCoAs)-Gerüst (12) durch Kristallstrukturanalyse identifiziert wurden. Sowohl in den Zwischenstufen 3 als auch in PMe2Ph-Derivaten der Cluster 1, 8 und 10 ließ sich die Chiralität NMR-spektroskopisch über die Diastereotopie der AsMe2-bzw. PMe2-Methylgruppen nachweisen.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 116 (1983), S. 3774-3793 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cluster Construction: Synthesis of Tetranuclear Clusters via AggregationTrinuclear clusters with EM3 frameworks (1-3, EM3 = SFeCo2, SRuCo2, PFeCo2, CCo3) can be connected via CO substitution with AsM′ units (M′ = Cr, Mo, W). The EM3-AsM′ intermediates 7-10 eliminate CO under appropriate conditions to form clusters 13-16 with tetrahedral M3M′ frameworks which bear ų3-E and ų2-AsMe2 ligands. The combinations M3M′ = FeCo2Mo, FeCo2W, RuCo2Mo, RuCo2W, Co3Mo, and Co3W were realized. Starting from trinuclear clusters 4, 5 with the chiral frameworks EM3 = SFeCoMo, SFeCoW, SRuCoMo, and SRuCoW by the same procedure via 11, 12 tetranuclear clusters 17, 18 with the frameworks M3M′ = FeCoMo2, FeCoW2, FeCoMoW, RuCoMo2, RuCoW2, and RuCoMoW are obtained. Among these are the first two clusters with four different metal atoms. The crystal structures of FeCo2MoS(AsMe2)Cp(CO)8 (13a), RuCo2MoS(AsMe2)Cp(CO)8 (14a), and FeCoMoWS-(AsMe2)Cp2(CO)7 (17b) were determined. The tetranuclear clusters show ligand fluxionality as shown by dynamic 1H NMR spectroscopy.
    Notes: An Dreikerncluster mit EM3-Gerüst (1-3, EM3 = SFeCo2, SRuCo2, PFeCo2, CCo3) lassen sich durch CO-Substitution AsM′-Einheiten (M′ = Cr, Mo, W) anbinden. Die EM3-AsM′-Zwischenstufen 7-10 spalten unter geeigneten Bedingungen CO ab, wobei Cluster 13-16 mit tetraedrischem M3M′-Gerüst entstehen, welches ų3-E- und ų-AsMe2-Liganden trägt. Es wurden die Kombinationen M3M′ = FeCo2Mo, FeCo2W, RuCo2Mo, RuCo2W, Co3Mo und Co3W verwirklicht. Ausgehend von Dreikernclustern 4, 5 mit den chiralen Gerüsten EM3 = SFeCoMo, SFeCoW, SRuCoMo und SRuCoW entstehen auf die gleiche Weise über 11, 12 Vierkerncluster 17, 18 mit den Gerüsten M3M′ = FeCoMo2, FeCoW2, FeCoMoW, RuCoMo2, RuCoW2, und RuCoMoW. Unter diesen sind die beiden ersten Cluster mit vier verschiedenen Metallatomen. Von FeCo2MoS(AsMe2)Cp(CO)8 (13a), RuCo2MoS(AsMe2)Cp(CO)8 (14a) und FeCoMoWS-(AsMe2)Cp2(CO)7 (17b) wurden die Kristallstrukturen bestimmt. Die Vierkerncluster zeigen eine Ligandenfluktuation, die durch dynamische 1H-NMR-Spektroskopie zu erfassen ist.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...