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  • 1
    Electronic Resource
    Electronic Resource
    Surface Enhanced Raman Spectroscopy on Carbon Filaments (2000)
    Springer
    Microchimica acta 133 (2000), S. 337-339 
    Details
    ISSN: 1436-5073
    Keywords: Key words: Raman spectroscopy; SERS; carbon; silver; plasmapolymer.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract.  A method for analysis of carbon-containing thin films by using surface enhanced Raman spectroscopy (SERS) is described. Thin films of boron nitride or silicon carbide which are deposited on carbon filaments were coated additionally with silver nanoparticles. A very thin plasma polymer film was deposited on the silver particles to give a better long time stability. Using these layers, very intensive carbon band were detected.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s006040070116
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  • 2
    Electronic Resource
    Electronic Resource
    Doppelt metalliertes Methanol. Alkohol-d1- und -d3 -Reagenzien (1980)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 113 (1980), S. 1290-1303 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Doubly Metalated Methanol.  -  Alcohol d1-and d3-ReagentsThe nucleophilic counterpart of the electrophilic hydroxymethylating protonated formaldehyde B is the hypothetical tautomer A, R=H, of methoxide. Experiments are described in which the generation of doubly metalated methanol C (= formaldehyde ketyl dianion) and its use as methanol d1-reagent are attempted. Treatment of stannylated methanol 1 with two equivalents of butyllithium furnishes a pentane-soluble reagent which hydroxymethylates electrophilic centers in moderate yields (umpolung of the formaldehyde a1-reactivity), see eq. (1) and table 3. Attempted isolation, 1H- and 13C-NMR measurements, and careful product analysis of the reaction with benzaldehyde (scheme 1 and table 2) support the view that the new reagent is actually not free lithium lithio-methoxide (2) but a tin derivative, see for instance 9 in eq. (2).  -  The O-silylated derivative 18 (=A, R=SiMe3) is likewise generated by Sn-Li-transmetallation, but cannot be trapped externally by electrophiles due to rapid Wittig rearrangement (→ 19 → 20). The readily accessible dilithio derivatives 21a and 23a can be employed as direct propanol and allyl alcohol d3-reagents, respectively.
    Notes: Das nucleophile Pendant zum elektrophilen Hydroxymethylierungsmittel B, dem protonierten Formaldehyd, ist das fiktive Methanolat-Tautomere A, R=H. Es werden Versuche zur Erzeugung des doppelt metallierten Methanols C (= Formaldehyd-Ketyldianion-Derivat) und dessen Verwendung als Methanol-d1-Reagenz beschrieben. Durch Umsetzung des stannylierten Methanols 1 mit zwei Äquivalenten Butyllithium erhält man ein pentanlösliches Reagenz, welches elektrophile Zentren in mäßigen Ausbeuten hydroxymethyliert (Umpolung der Formaldehydreaktivität), Gl. (1) und Tab. 3. Isolierungsversuche, 1H- und 13C-NMR-Messungen sowie sorgfältige Produktanalyse der Reaktion mit Benzaldehyd (Schema 1 und Tab. 2) stützen die Hypothese, daß das erzeugte Reagenz nicht das freie Lithium-lithiomethanolat (2), sondern ein Sn-Derivat, z. B. 9 in Gl. (2) sein dürfte.  -  Das ebenfalls durch Sn/Li-Transmetallierung erzeugte O-Silylderivat 18 [=A, R=Si(CH3)3] läßt sich wegen zu schneller Wittig-Umlagerung (→ 19 → 20) nicht extern mit Elektrophilen abfangen, während die leicht zugänglichen Dilithiumderivate 21a und 23a als direkte Propanol- bzw. Allylalkohol-d3-Reagenzien fungieren.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19801130409
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  • 3
    Electronic Resource
    Electronic Resource
    Direkte ortho-Metallierung von Benzylalkoholen Eine neuartige Herstellung von ortho-substituierten Benzylalkoholen (1980)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 113 (1980), S. 1304-1319 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Direct ortho-Metalation of Benzyl Alcohols. A Novel Method of Preparing ortho-Substituted Benzyl AlcoholsBenzyl alcohol and other phenylcarbinols (8a - 11a), including α-tetralol (12a), are doubly deprotonated by excess n-butyllithium/TMEDA in pentane to give lithium ortho-lithioalkoxides (2, 8b - 12b). Alkylations (→ 3a - d, table 1), reactions with heteroelectrophiles (→ 3e - k, table 2) and with carbonyl compounds (→ 6, 13 - 17, tables 3 and 4), as well as subsequent reactions of the primary adducts (→ phthalanes 7, table 3) furnish a large variety of ortho-substituted benzyl alcohol derivatives. The scope and limitations of the dilithioorganyls (sections B and C), their mode of formation (section A), and attempts to doubly metalate 2-phenylethanol [section D, equation (4)] are discussed.
    Notes: Benzylalkohol und andere Phenylcarbinole (8a - 11a), einschließlich α-Tetralol (12a), werden von überschüssigem Butyllithium/TMEDA in Pentan zu Lithium-ortho-lithioalkoholaten (2, 8b - 12b) doppelt deprotoniert. Alkylierungen (→ 3a - d, Tab. 1), Umsetzungen mit Heteroelektrophilen (→ 3e - k, Tab. 2) und Carbonylverbindungen (→ 6, 13 - 17, Tab. 3 und 4) sowie Folgereaktionen der Primäraddukte (→ Phthalane 7, Tab. 3) liefern eine Vielzahl verschiedenartigster, ortho-substituierter Benzylalkoholderivate. Die Anwendungsgrenzen der Dianionderivate (Abschnitte B und C), ihr Bildungsmechanismus (Abschnitt A) und Versuche zur Doppelmetallierung von 2-Phenylethanol [Abschnitt D, Gl. (4)] werden diskutiert.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19801130410
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  • 4
    Electronic Resource
    Electronic Resource
    Direkte Hydroxymethylierung zu verzweigten Zuckern mit einem Hydroxymethyl-d1-Reagenz (1980)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 113 (1980), S. 2055-2061 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Direct Hydroxymethylation to Branched-chain Sugars by means of a Hydroxymethyl-d1 ReagentBlocked ketoses react with the dianion 2 directly to hydroxymethylation products. Butylation products have been found as by-products. The procedure in which the yields are limited can be used favourably in special cases.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19801130545
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  • 5
    Electronic Resource
    Electronic Resource
    α-Heterosubstituierte Organyllithiumverbindungen durch Selen/Lithium-Austausch; gezielte Kopplung von Carbonyl-verbindungen (1977)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1977 (1977), S. 846-858 
    Details
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: α-Heterosubstituted Organyllithium Compounds by Selenium/Lithium-Exchange; Directed Coupling of Carbonyl CompoundsThe preparation of phenylseleno derivatives 1-4 and 6 is described. Se/Li-exchange with butyl- and tert-butyllithium removes the heteroatom free substituent from 1-3 and 8a; the sulfur derivative 10a undergoes the same transformation. The α-seleno- and α-thioalkyl-lithium derivatives 5 and 11 are generated in high yields from 4 and 6, respectively, as shown by their reactions with carbonyl compounds to give alcohols 12 and 16. According to scheme 1, the allylic alcohols 17, 18, and 20, as well as the olefin 21 and the epoxide 22 are obtained.
    Notes: Die Phenylselenderivate 1-4 und 6 wurden hergestellt.  -  Während beim Versuch der Transmetallierung von 1-3 sowie 8a mit Butyl- oder tert-Butyllithium stets der heteroatomfreie Substituent am Selen ausgetauscht wird, was auch beim Thioether 10a der Fall ist, entstehen aus 4 und 6 die α-Seleno- und α-Thioalkyllithiumderivate 5 bzw. 11. Dies wird durch deren Umsetzung zu den Alkoholen 12 und 16 bewiesen.  -  Nach Schema 1 wurden die Allylalkohole 17, 18 und 20, sowie das Olefin 21 und das Epoxid 22 synthetisiert.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.197719770514
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  • 6
    Electronic Resource
    Electronic Resource
    Treatment of noisy data from distribution analysis using models from time-series analysis (1990)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 337 (1990), S. 802-807 
    Details
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Data from distribution-analysis are often affected by a high noise. The described information about elemental distribution is frequently hidden in this noise far below Kaiser's limit of detection with signal to noise of 3. To gain this useful information under these conditions (S/N ≪3) models from time-series-analysis (especially quality-control, process-control) have proven a powerful tool. The adaption of these models for the treatment of 1d-, 2d-, and 3d- distribution-analyses as well examples for application are presented.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00322255
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  • 7
    Electronic Resource
    Electronic Resource
    Lithium-ortho-lithiobenzylalkoholate (1978)
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 90 (1978), S. 553-554 
    Details
    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
    URL: http://dx.doi.org/10.1002/ange.19780900715
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  • 8
    Electronic Resource
    Electronic Resource
    Doppelt metalliertes Methanol, ein nucleophiles HydroxymethylierungsreagensTeil der geplanten Dissertation von N. Meyer, Universität Gießen. N. Meyer dankt der Studienstiftung des Deutschen Volkes für ein Stipendium.  -  Diese Arbeit wurde vom Fonds der Chemischen Industrie unterstützt. Der Firma Schering, Bergkamen, danken wir für Tributylzinnchlorid. (1976)
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 88 (1976), S. 484-484 
    Details
    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
    URL: http://dx.doi.org/10.1002/ange.19760881413
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  • 9
    Electronic Resource
    Electronic Resource
    Doubly Metalated Methanol - A Nucleophilic Hydroxymethylation ReagentPart of projected thesis of N. Meyer, Universität Giessen. N. M. thanks the Studienstiftung des Deutschen Volkes for a grant. - This work was supported by the Fonds der Chemischen Industrie. We are grateful to the Schering company, Bergkamen, for a gift of tributyltin chloride. (1976)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 15 (1976), S. 438-438 
    Details
    ISSN: 0570-0833
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.197604381
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  • 10
    Electronic Resource
    Electronic Resource
    Lithium ortho-Lithiobenzyl Alkoxides (1978)
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 17 (1978), S. 521-522 
    Details
    ISSN: 0570-0833
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/anie.197805211
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