Library

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
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 40 (1847), S. 448-448 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Proton-NMR. spectra of amino- and hydroxypyrimidines including biologically important bases have been measured in four solvents: CF3COOH, CF3COOH—SO2, FSO3H and FSO3H—SbF5-SO2 at 27° and -55°C. In CF3COOH mono-cations are formed, whereas in FSO3H and FSO3H—SbF5-SO2 double protonation occurs. In each case the structures of the protonated species are derived from the chemical shifts of CH, NH and OH protons and proton-proton spin coupling constants. A combination of the measurements described leads to a complete assignment of all proton resonances of the protonated pyrimidines. This approach is also recommended for the structural determination of heterocyclic compounds.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Proton NMR. spectra of purine, adenine, guanine and methylsubstituted guanines have been measured in CF3COOH, FSO3H and FSO3H—SbF5—SO2 at 27° and low temperatures. These conditions permit to study multiple protonation of purines, using chemical shifts of CH, NH and OH protons. The spectra of mono-, di- and tri-cations are described and fully assigned.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 64 (1848), S. 293-293 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 49 (1850), S. 191-192 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 2 (1869), S. 108-110 
    ISSN: 0365-9496
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 0268-2605
    Keywords: carbohydrate-modified phenylsiloxane ; surfactants ; wetting behaviour ; superspreading ; Chemistry ; Industrial Chemistry and Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The dynamic wetting behaviour on a perfluorinated, low-energy solid has been investigated for a carbohydrate-modified phenylsiloxane surfactant. The surfactant concentration, the rate of interface generation and the [solid/liquid interface area] : [liquid/vapour interface area] ratio were varied systematically. Dynamic data for the liquid/vapour (γlv) and solid/liquid (γsl) interfacial tension as well as their Lifshitz-van der Waals and donor-acceptor contributions were determined under strictly controlled conditions. Since γsl reacts sensitively to variations of the surfactant concentration and the rate of interface generation, the covering of the liquid/non-polar solid interface is assumed to be a spreading limiting factor. The corresponding γlv values remain constant and close to those obtained under equilibrium conditions. Copyright © 1998 John Wiley & Sons, Ltd.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Halosilane Adducts. XIV. Neutral Ligand Complexes of Silicon Containing Six N-Donor Atoms[Si · 3 bipy]4+ is obtained in high yield by the oxidation of Si · 3 bipy with the halogens. [Si · 3 bipy]I4 may also be prepared by directly reacting SiI4 and bipy in the melt. Phen and SiI4 yield [Si · 3 phen]I4 under the same conditions. Mimi and vimi and dimi react with SiI4 in CHCl3 to give [Si · 6 L]I4 (L = mimi, vimi) and [Si · 3 dimi]I4. Thiazole and pyridine and 4-dimethylaminopyridine, on the other hand, yield 1:4 complexes, isoxazole does not react at all. The complex stoichiometry is dependant on the basicity and the structure of the ligands. The 1:4 complexes are easily hydrolysed whereas the N-hexacoordinated complexes are very resistant against solvolysis. They are soluble in water without decomposition. Spectroscopic investigations (i.r., u.v., 1H-nmr) prove the presence of octahedral complex cations of the charge +4 according to the given formulae for the solid and dissolved compounds. Complete anion-exchange is possible. Using ion-exchangers the complexes [Si · 6(3)L](ClO4)4 are obtained.
    Notes: [Si · 3 bipy]4+ wird in hoher Ausbeute durch Oxydation von Si · 3 bipy mit Halogen erhalten. Die Darstellung von [Si · 3 bipy]I4 gelingt auch durch direkte Reaktion von SiI4 und bipy in der Schmelze. Mit phen wird unter gleichen Bedingungen [Si · 3 phen]I4 gebildet. 1-Methyl(Vinyl)-imidazol (mimi, vimi) und 1,1′-Dimethyl-2,2′-diimidazol (dimi) reagieren mit SiI4 in CHCl3 zu [Si · 6 L]I4 (L = mimi, vimi) und [Si · 3 dimi]I4. Mit Thiazol, Pyridin und 4-Dimethyl-aminopyridin werden 1:4 Komplexe, mit Isoxazol keine Reaktion erhalten. Die Komplexstöchiometrie hängt von Basizität und Struktur der Liganden ab. Die 1:4 Komplexe sind hydrolyseempfindlich, die N-hexakoordinierten Komplexe sehr solvolysebeständig. Sie sind unzersetzt in Wasser löslich. Spektroskopische Untersuchungen (IR, UV, 1H-NMR) weisen für die festen und gelösten Titelverbindungen oktaedrische Komplexkationen der Ladung 4+ entsprechend den gegebenen Formeln nach. Über Ionenaustauscher ist vollständiger Anionenaustausch möglich. Mit dieser Methode werden die Komplexe [Si · 6(3)L](ClO4)4 dargestellt.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 0268-2605
    Keywords: siloxanes ; carbohydrate modified ; surfactants ; saccharide ; Chemistry ; Industrial Chemistry and Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New siloxanyl-modified carbohydrate surfactants of the amide and glycoside type have been synthesized by coupling between defined as well as higher-molecular-weight siloxanes and carbohydrate structures via spacers of different lengths and hydrophilic power. Linear and branched monohydrogen di-, tri-, tetra- and penta-siloxanes and polyhydrogen siloxanes as well as mono- and di-saccharide lactone structures have been found to be good starting materials for the synthesis of amides, often in quantitative yield, whereas glycosides had to be prepared in low-yield multistep sequences including protection/deprotection steps. Selected strategies were applied to polysiloxanes yielding quantitatively a broad variety of carbohydrate-modified comb-like structures. The new substances were characterized by means of 13C NMR spectroscopy, GC, capillary GC, GC-MS coupling and elemental analysis.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 0268-2605
    Keywords: surfactants ; carbohydrate ; carbosilane ; silane ; wetting ; surface tension ; Chemistry ; Industrial Chemistry and Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of carbohydrate surfactants bearing carbosilane, silane, polysilane and non-permethylated siloxane moieties is described. These surfactants consist of three structural elements: (1) a silicon-containing moiety, (2) a spacer and (3) a carbohydrate unit. Additionally two different types of mixed structures have been synthesized: (a) single-chained carbosilane-siloxane surfactants and (b) double-chained combinations of carbo- silanes, silanes and siloxanes. The wetting behaviour of the key intermediates, the allyl glycidyl derivatives, has been investigated by static surface tension (γlv, σ) and wetting tension (γsv-γsl, α) measurements on a non-polar perfluorinated surface (FEP® plate). The contact angles obtained for these pure liquids are not a linear function of the surface tension but depend on the polarity of the substructures. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...