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  • 1
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Analytica Chimica Acta 266 (1992), S. 39-42 
    ISSN: 0003-2670
    Keywords: Aminoaza-3-bicyclo[3.3.0]octane ; UV-Visible spectrophotometry
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1434-4475
    Keywords: Synthesis ; 3,4-Diazabicyclo[4,3,0]non-2-ene ; N,N′-Azo-3-azabicyclo[3,3,0]octane ; Diazene ; Hydrazine ; NMR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung 3,4-Diazabicyclo[4,3,0]-non-2-en und N,N′-Azo-3-azabicyclo[3,3,0]oktan sind die Hauptreaktionsprodukte der Oxidation von N-Amino-3-azabicyclo[3,3,0]oktan durch Chloramin. Die Interaktion führt übergangsweise zur Bildung eines gesättigten bizyklischen Aminonitrens (Diazens). Oberhalb despH-Wertes 13 lagert sich das Diazen intramolekular um und bildet ein Hydrazon. Unterhalb despH-Wertes 9 fällt ein weißer Niederschlag aus (Tetrazen), der von einer Dimerisierung zwischen for molekularen und protonierten Form von Aminonitren herrühren dürfte. Für die dazwischenliegenden Werte (9 〈pH 〈 13) erhält man eine Mischung aus beiden Verbindungen. Sie wurden isoliert und mit Hilfe von UV, GC/MS, IR, und1H/13C-NMR untersucht. Ein Reaktionsmechanismus wird vorgeschlagen.
    Notes: Summary 3,4-Diazabicyclo[4,3,0]non-2-ene and N,N′-azo-3-azabicyclo[3,3,0]octane are the main products of the oxidation of N-amino-3-azabicyclo[3,3,0]octane by chloramine. The reaction leads to the transient formation of a saturated bicyclic aminonitrene (diazene). AtpH 〉 13, the diazene undergoes an intramolecular rearrangement to afford a hydrazone. AtpH 〈 9, a white solid is formed resulting from the dimerization of the molecular and protonated forms of the aminonitrene. At intermediatepH-values, a mixture of both species is obtained. They have been isolated and characterized by UV, GC/MS, IR, and1H/13CNMR. A reaction mechanism is proposed.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 27 (1995), S. 757-768 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the degradation of N-amino-3-azabicyclo[3,3,0]octane by chloramine has been studied by GC and HPLC in stoichiometric conditions in a solution buffered with NaOH/KH2PO4 and Na2B4O7.10 H2O between pH = 10.5 and 13.5. The second-order reaction exhibits specific acid catalysis which indicates competitive oxidation between the haloamine and the neutral and ionic forms of the bicyclic hydrazine. The enthalpy and entropy of activation were determined at pH = 12.89.In a nonbuffered solution, the interaction is autocatalyzed due to acidification of the mixture by the ammonium ions. In basic medium, the reaction forms an endocyclic hydrazone. A mathematical treatment based on an implicit equation allows a quantitative interpretation of all the phenomena observed over the above pH interval. This takes both the acid/base dissociation equilibria and the alkaline hydrolysis of the chloro-derivative into account. © 1995 John Wiley & Sons, Inc.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The chlorine transfer reaction between 3-azabicyclo[3,3,0]octane “AZA” and chloramine was studied over pH 8-13 in order to follow both the amination and halogenation properties of NH2Cl. The results show the existence of two competitive reactions which lead to the simultaneous formation of N-amino- and N-chloro- 3-azabicyclo[3,3,0]octane by bimolecular kinetics. The halogenation reaction is reversible and the chlorine derivative obtained, which is thermolabile and unstable in the pure state, was identified by electrospray mass spectrometry. These phenomena were quantified by a reaction between neutral species according to an apparent SN2-type mechanism for the amination process and a ionic mechanism involving a reaction between chloramine and protonated amine for the halogenation process. Amination occurs only in strongly basic solutions (pH ≥ 13) while chlorination occurs at lower pH's (pH ≤ 8). At intermediate pH's, a mixture of these two compounds is obtained. The relative proportions of the products are a function of intrinsic rate constants, pH and pKa of the reactants. The rate constants and thermodynamic activation parameters are the following: k1 = 45.5 × 10-3 M-1 s-1; ΔH10# = 59.8 kJ mol-1; ΔS10# = - 86.5 J mol-1 K-1 for amination; k2 = 114 × 10-3 M-1 s-1; ΔH20# = 63.9 kJ mol-1; and ΔS20# = - 48.3 J mol-1 K-1 for chlorination. The ability of an interaction corresponding to a specific(NH3Cl+/RR′NH) or general (NH2Cl/RR′NH) acid catalysis has been also discussed. © 1997 John Wiley & Sons, Inc.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The formation of 3-azabicyclo[3,3,0]oct-2-ene in the course of the synthesis of N-amino-3-azabicyclo[3,3,0]octane using the Raschig process results from the following two consecutive reactions: chlorine transfer between the monochloramine and the 3-azabicyclo[3,3,0]octane followed by a dehydrohalogenation of the substituted haloamine. The kinetics of the reaction were studied by HPLC and UV as a function of temperature (15 to 44°C), and the concentrations of NaOH (0.1 to 1 M) and the chlorinated derivative (1 to 4×10-3 M). The reaction is bimolecular (k=103×10-6 M-1 s-1; ΔH0#=89 kJ mol-1; and ΔS0#=-33.6 J mol-1 K-1) and has an E2 mechanism. The spectral data of 3-azabicyclo[3,3,0]oct-2-ene were determined. IR, NMR, and ES/MS analysis show dimerization of the water-soluble monomer into a white insoluble dimer. © 1998 John Wiley & Sons, Inc. Int J Chem Kinet: 30: 129-136, 1998.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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