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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 106 (1973), S. 1226-1237 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Tetraorganofluorophosphoranes, R4PFA series of synthetic procedures for the preparation of tetramethyl-, tetraethyl-, methyltri-butyl-, and methyltriphenyl-fluorophosphoranes have been developed, using the corresponding ylids or silylated ylids as starting materials. Anhydrous hydrogen fluoride, KHF2, or NH4F were employed as fluorinating agents (eq. (l)-(3), e.g.). The tetraorganofluoro-phosphoranes exist as ionic solids [as with (CH3)4PF] or as molecular species containing pentacoordinate phosphorus atoms [as with (C2H5PF].  -  For fluorotetramethylantimony, a known molecular compound, an improved, and more simple method of preparation has been found. (CH3)4SbF forms addition compounds with (CH3)4PF and CH3(n-C4H9PF, the phosphorus component apparently being in the tetracoordinate onium state. R4PF compounds are good fluorinating agents for halocarbons and halosilanes (eq. (7)).
    Notes: Für Tetramethyl-, Tetraäthyl-, Methyltributyl- und Methyltriphenyl-fluorphosphoran wurden einfache Syntheseverfahren ausgearbeitet, die von den zugehörigen salzfreien Yliden oder ihren Silylderivaten ausgehen. Als HF-Komponenten sind entweder Fluorwasserstoff selbst oder KHF2 bzw. NH4F verwendbar (z. B. Gl. (1)-(3)). Die Tetraorganofluorphosphorane sind zum Teil ionisch aufgebaut [vor allem (CH3)4PF], zum Teil Molekülverbindungen mit pentakoordinierten Phosphoratomen [wie bei (C2H5)4PF].  -  Für das schon bekannte Fluortetramethylantimon wurde die Darstellungsmethode verbessert. (CH3)4SbF reagiert mit (CH3)4PF und CH3(n-C4H9)3PF zu salzartigen Addukten, in denen die Phosphorkomponente als Onium-Gruppierung auftritt. R4PF-Verbindungen fluorieren sowohl Halogenkohlenwasserstoffe als auch Halogensilane (Gl. (7)).
    Additional Material: 1 Ill.
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 105 (1972), S. 1084-1086 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 107 (1974), S. 1420-1427 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Reactions of Phosphorus Ylids with Excess Alkohol and AlkanethiolThe alkoxytetraalkylphosphoranes of the formula R4POR′, obtained from equimolar amounts of ylid and alkohol, which contain pentacoordinate phosphorus atoms, are converted into ionic products (1 - 7) by addition of excess alkohol. In these compounds phosphonium cations R4P⊕ are accompanied by hydrogen-bonded hydrogenalkoholate anions of the types [R′O…H…OR′]⊖, [H2(OR′)3]⊖, and [H3(OR′)4]⊖. This structure is proposed on the basis of n.m.r., i.r., and Raman-spectroscopic data. With ylids and alkanethiols only salt-like products R4P⊕RS⊖ are formed.
    Notes: Die aus äquimolaren Mengen von Yliden und Alkoholen zugänglichen, kovalent gebauten Alkoxytetraalkylphosphorane R4POR′ mit pentakoordinierten Phosphoratomen werden durch Addition von überschüssigem Alkohol in die Produkte 1 - 7 verwandelt, in welchen Phosphonium-Kationen R4P⊕ den wasserstoffbrückenverknüpften Hydrogenalkoholat-Anionen vom Typ [R′O…H…OR′]⊖, [H2(OR′)3]⊖ und [H3(OR′)4]⊖ gegenüberstehen. Der Strukturvorschlag stützt sich auf NMR-, IR- und Raman-spektroskopische Untersuchungen. Aus Yliden und Alkanthiolen entstehen nur die salzartigen Phosphonium-alkanthiolate R4 P⊕RS⊖.
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 106 (1973), S. 1238-1250 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Tetraorganoalkoxyphosphoranes, R4POR′Trimethylmethylenephosphorane reacts with methanol and ethanol to give methoxy- and ethoxytetramethylphosphorane, respectively. According to molecular weight determinations and 1H- as well as 31P n.m.r. investigations these two compounds have a pentacoordinate molecular structure. Below -65°C the five ligands occupy discrete positions of a trigonal bipyramidal geometry. For the first time alkyl groups are found in an axial position. (CH3)4POCH3 and (CH3)4POC2H5 decompose above ca. 130°C to yield (CH3)3PO and alkane. This type of decomposition is encountered with the products obtained from (CH3)3P=CH2 and isopropyl and tert-butylalcohol already at room temperature. With trimethylsilanol a crystalline 1 : 1 adduct is formed at 0°C, which decomposes to (CH3PO, CH4, and (CH3)3SiOSi(CH3)3. The product formed with phenol is assigned an ionic structure (CH3)4P ⊕ OC6H5⊖.  -  Alkoxyphosphoranes with pentacoordinate phosphorus atoms (5-7) are also obtained from methylenetriphenylphosphorane and alcohols. Thermal decomposition in this case leads to the phosphine CH3P(C6H5)2 and alkyl aryl ethers, e.g. anisol for 5 (eq. (12)). tert-Butylalcohol does not form a phosphorane with (C6H5)3P=CH2. Only a proton exchange process involving the OH, CH3, and CH2 hydrogens is observed. The compounds 5-7 were also shown to dissociate in solution and to undergo this exchange, probably through the equilibrium according to eq. (6).
    Notes: Trimethylmethylenphosphoran reagiert mit Methanol und äthanol zu Methoxy- bzw. äthoxytetramethylphosphoran, denen nach Molekülmasse-Bestimmungen, vor allem aber nach den 1H- und 31P-NMR-Spektren eine Struktur mit pentakoordinierten Phosphoratomen zukommt. Unterhalb von -65°C können den fünf Liganden diskrete Positionen an einer trigonal-bipyramidalen Struktur zugewiesen werden. Erstmals werden Alkylgruppen in axialer Position gefunden. (CH3POCH3 und (CH3)4POC2H5 zerfallen ab ca. 130°C in (CH3)3PO und Alkan. Diese Zersetzung tritt mit den Produkten aus (CH3)3P=CH2 und Isopropylalkohol und tert-Butylalkohol schon bei Raumtemperatur ein. Mit (CH3)3SiOH entsteht bei 0°C eine kristalline 1 : 1-Verbindung, die sich zu (CH3)3PO, (CH3)3SiOSi(CH3)3 und CH4 zersetzt. (CH3)3P=CH2 bildet mit Phenol ionisches (CH3)4P⊕OC6H5⊖.  -  Aus Methylentriphenylphosphoran und Alkoholen entstehen ebenfalls Alkoxyphosphorane mit pentakoordinierten Zentralatomen (5-75-7). Ihr thermischer Zerfall führt überraschend zum Phosphin CH3P(C6H5)3 und Alkylaryläthern, z. B. mit 5 zu Anisol (Gl. (12)). tert-Butyl-alkohol bildet mit (C6H5)3P=CH2 kein Phosphoran mehr. Hier tritt lediglich noch der Protonenaustausch zwischen OH- und CH3- sowie CH2-Gruppe ein. Auch die Phosphorane 5-7 sind in Lösung teilweise in Umkehrung der Bildungsgleichung (6) dissoziiert und zeigen diesen Austausch.
    Additional Material: 2 Ill.
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 85 (1973), S. 345-346 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 84 (1972), S. 166-167 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 7
    ISSN: 0570-0833
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 11 (1972), S. 145-146 
    ISSN: 0570-0833
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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