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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 120 (1921), S. 261-266 
    ISSN: 0863-1786
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 160 (1988), S. 1-15 
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Poly(tetramethylenadipat)diol mit einer Molmasse von 2000 wurde bei Temperaturen von 60 und 80°C in Gegenwart von Wasser bzw. 1,4-Butandiol sowie den gebräuchlichsten PUR-Katalysatoren (Dabco und Dibutylzinndilaurat) gelagert und die Solvolyse untersucht. Die Geschwindigkeit der Solvolyse nimmt mit steigender Temperatur deutlich zu. Die Alkoholyse wird durch Dibutylzinndilaurat weitaus stärker katalysiert als durch 1,4-Diazabicyclo[2.2.2]oktan. Die Hydrolyse verläuft langsamer, da vermutlich die Katalysatoren bei diesem Prozeß desaktiviert werden. Die mechanischen Eigenschaften von Polyurethanen, die mit den partiell abgebauten Diolen hergestellt wurden, korrelieren gut mit der Abnahme der Molmasse.
    Notes: Poly(tetramethylene adipate)diol having a molar mass of 2000 was stored at temperatures of 60 and 80°C in the presence of water or 1,4-butanediol and a common PUR-catalyst like 1,4-diazabicyclo [2.2.2]octane (DABCO) or dibutyltindilaurate (DBTL) and the solvolysis was investigated. The rate of solvolysis is low at 60°C except for DBTL and shows a drastic increase at 80°C. In the alcoholysis reaction DBTL is a much more active catalyst than DABCO. The rate of hydrolysis is slower probably because the catalysts are deactivated by the acidic products formed in this process. The mechanical properties of polyurethanes made from the degraded polyols are in good correlation with the decrease in molar mass.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1979 (1979), S. 1205-1211 
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Stereochemistry of 3,3′-(1,2-Diethylethylene)diphenols1-Chloro-1-(3-methoxyphenyl)propane 5 was converted by C-C coupling in to a mixture of dia-stereomeric 3,4-bis(3-methoxyphenyl)hexanes 6, which could be separated by crystallization into the meso- and rac-compounds 6a and 6b, respectively. After ether cleavage meso-3,3′-(1,2-di-ethylethylene)diphenol and rac-3,3′-(1,2-diethylethylene)diphenol (2a and 2b) were obtained; the latter was resolved via the diastereomeric (+)- and (-)-3,3′-(1,2-diethylethylene)diphenyl-3,4-bis[3-D-(+)-3-bromo-2-oxo-8-bonanylsulfonates] (7) into (+)-3,3′-(1,2-diethylethylene)diphenol and (-)-3,3′-(1,2-diethylethylene)diphenol [(+)-2b and (-)-2b]. The absolute configuration of the optical enantiomers could be established by means of oxidative degradation of (+)-2b.
    Notes: Aus 1-Chlor-1-(3-methoxyphenyl)propan (5) wurde durch C-C-Verknüpfung das Diastereomerenpaar 3,4-Bis(3-methoxyphenyl)hexan 6 erhalten. Durch Kristallisation konnten hieraus die meso- und die rac-Verbindungen 6a bzw. 6b isoliert warden. Die Spaltung der Ether führte zu meso-3,3′-(1,2-Diethylethylen)diphenol und rac-3,3′-(1,2-Diethylethylen)diphenol (2a bzw. 2b). Verbindung 2b wurde über die diastereomeren (+)- und (-)-3,3′-(1,2-Diethylethylen)diphenyl-3,4-bis[3-D-(+)-3-brom-2-oxo-8-bornanylsulfonate] (7) in (+)-3,3′-(1,2-Diethylethylen)diphenol und (-)-3,3′-(1,2-Diethylethylen)diphenol [(+)-2b bzw. (-)-2b] aufgetrennt. Die absolute Konfiguration der optischen Antipoden wurde durch oxidativen Abbau von (+)-2b ermittelt.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Constituents of the Horse Chestnut, VII 1). O-Isopropylidene Derivatives of Protoescigenin, Barringtogenol C,and their 21-Angelic (Tiglic) Acid and 28-Angelic (Tiglic) Acid EstersThe O-isopropylidene derivatives of protoescigenin barringtogenol C, and their 21-angelic (tiglic) acid and 28-angelic(tiglic) acid esters have been prepared by reaction with acetone/p-toluenesulfonic acid. The substances were isolated by column chromatography and their structures have been determined.
    Notes: O-Isopropyliden-Derivate von Protoäscigenin, Barringtogenol C und von deren 21- bzw. 28-Angelika(Tiglin)säureestern werden durch Umsetzung mit Aceton/p-Toluolsulfonsäure hergestellt, durch Säulenchromatographie isoliert und in ihrer Struktur bestimmt.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 83 (1971), S. 938-938 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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