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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Chemie 113 (1982), S. 1239-1244 
    ISSN: 1434-4475
    Keywords: Allyl alcohol ; Kinetics ; Mechanism ; Oxidation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die Kinetik der Oxidation von Allylalkohol mitN-Bromsuccinimid (NBS) wurde bei 35 °C in wäßrigem Medium untersucht. Die Reaktion zeigt erste Ordnung gegenüberNBS und Allylalkohol. Bei relativ hoher Säurekonzentration zeigt sich keine Änderung der Reaktionsgeschwindigkeit, bei niedriger Säurekonzentration wird die Reaktionsgeschwindigkeit beträchtlich erhöht. Es wurde kein primärer Salzeffekt festgestellt. Bei varriierender Quecksilberacetatkonzentration bleibt die Reaktionsgeschwindigkeit gleich, bei Abwesenheit von Quecksilberacetat wird jedoch die Geschwindigkeitskonstante erhöht. Die kinetischen Parameter,E a, derArrheniusfaktorA, ΔH ≠, ΔG ≠ und ΔS ≠ wurden bestimmt. Ein Geschwindigkeitsgesetz in Übereinstimmung mit den experimentellen Befunden wurde abgeleitet und ein Mechanismus vorgeschlagen.
    Notes: Abstract The kinetics of oxidation of allyl alcohol byN-bromosuccinimide (NBS) has been studied at 35 °C in aqueous medium. The reaction shows first order dependence on bothNBS and allyl alcohol. In fairly high acid concentration, there is no change in the rate of the reaction but at low acid concentration, the rate is considerably enhanced. There is no primary salt effect. At varying mercuric acetate concentrations, the rate constant remains the same. But in the absence of mercuric acetate, the rate is enhanced. The kinetic parameters,E a,Arrhenius factorA, ΔH≠, ΔG≠ and ΔS≠ have been calculated. A rate law in agreement with experimental results has been derived. A mechanism is proposed.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1434-4475
    Keywords: Cyclohexanol ; Kinetics ; Mechanism ; Oxidation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die Kinetik der Oxidation von Cyclohexanol mitCBT wurde bei 40°C in 50% wäßriger Essigsäure untersucht. Die Reaktion war sowohl bezüglich Oxidationsmittel als auch Substrat von erster Ordnung. Die Reaktionsgeschwindigkeit wird mit zunehmender Säurekonzentration (AcOH) erhöht. Die kinetischen Parameter wurden bestimmt und ein passender Mechanismus wird vorgeschlagen.
    Notes: Abstract The kinetics of oxidation of cyclohexanol by 1-Chlorobenzotriazole (CBT) has been studied at 40°C in 50% aqueous acetic acid. The reaction is first order with respect to oxidant and first order with respect to substrate. The rate is found to increase with increase in acid concentration and percentage ofAcOH in the mixture. The kinetic parameters have been calculated. A suitable mechanism is proposed.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Reaction kinetics and catalysis letters 40 (1989), S. 369-374 
    ISSN: 1588-2837
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Abstract Перборатное окисление хинола в водной уксусной кислоте имеет певый порядок по отношению к перборату, нулевой порядок по отношению к хинолу и иервый порядок по отношению к H+. Это окисление бытрее пероксидного окисления. Полагали, что ступенью, лимитируюшей скорость реакции, является расшепление протонированной перборатной кнслоты.
    Notes: Abstract The perborate oxidation of quinol in aqueous acetic acid is first order with respect to perborate, zero order with respect to quinol, and first order with respect to H+. The oxidation is faster than H2O2 oxidation. Breakdown of protonated perboric acid is suggested as the rate-limiting step.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 3 (1990), S. 235-238 
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The reactions of N-bromosuccinimide (NBS) with allyl and crotyl alcohols in aqueous methanol are first order in NBS. Allyl alcohol displays a zero-order dependence whereas crotyl alcohol exhibits a Michaelis-Menten-type dependence on substrate concentration. The NBS-allyl alcohol reaction is inhibited by H+ whereas the NBS-crotyl alcohol reaction is independent of [H+]. However, both are fast in the absence of acid. The rates are unaffected by the addition of neutral salt and succinimide. The reaction of NBS with crotyl alcohol exhibits a positive dielectric effect whereas allyl alcohol displays no such effect. Inhibition by HgII is observed in the crotyl alcohol reaction but not with allyl alcohol. 3-Bromo-2-methoxypropan-1-ol is the product of the allyl alcohol reaction but a mixture of 2-bromo-3-methoxybutan-1-ol and 2-bromobutane-1,3-diol in the crotyl alcohol reaction. In the allyl alcohol reaction the formation of solvated bromonium ion and of HOBr is suggested as rate-limiting steps. In the crotyl alcohol reaction, rate determining breakdown of an NBS-crotyl alcohol complex, formed in a fast pre-equilibrium, is proposed.
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 21 (1989), S. 423-430 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of oxidation of a number of ortho, meta, and para substituted S-phenylmercaptoacetic acids by N-Chloro-3-Metyl-2,6-Diphenylpiperidin-4-one (NCP) has been studied in buffered ethanol-water (75:25 v/v) of pH 5.46. The reaction is of first order each in [oxidant] and [substrate]. The rate constant decreases with increase in pH from 5.22 to 5.70. The reaction is accelerated by electron releasing and retarded by electron withdrawing substitutents. The ρ value obtained for this reaction is -1.88 at 10°C with a good correlation coefficient of 0.99 showing an electron deficient transition state. The effect of ortho substitutents also is discussed in detail.
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 22 (1990), S. 415-426 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of chlorination of a number of ortho-, meta-, and para-substituted phenols by N-chloro-3-methyl-2,6-diphenylpiperidin-4-one (NCP) in acid medium have been investigated. The reaction is of first order with respect to oxidant and the order with respect to the substrate varies depending on the nature of the substituent present in the ring. With cresols and m-chlorophenol the order is unity, with p-methoxyphenol, zero and with the other phenols, a fraction. Isokinetic and Exner plots give straight lines with fine correlation coefficients. But the Hammett plot gives a curve that was concave downwards, instead of a straight line. The observed Hammett plot deviation has been accounted for suitably. Regression analyses of the rate data of ortho-substituted phenols by using Taft and Charton equations to separate steric effects from electronic effects have been carried out. In this reaction, the localized electronic effect plays a major role while steric and resonance effects play a minor role.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 129-139 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of oxidation of methyl phenyl sulfoxide by chloramine-T (CAT) has been studied in buffered ethanol-water (1:1 v/v) of pH 7.0. The reaction was found to follow no simple-order kinetics. A possible mechanism is suggested involving three rate-controlling steps: (1) the reaction between RNHCl (R = CH3C6H4SO2) and the sulfoxide, (2) the disproportionation of RNHCl, and (3) the reaction between RNCl2 and the sulfoxide. A mixed-order rate law is derived as rate/[C][SO] = k1 + Kdk2[C]/[SA]. The rate law is found to be obeyed for the meta- and para-substituted phenyl methyl sulfoxides also. The ρ value is obtained using Hammett's σ constants. The ρ values obtained for the attack of both RNHCl and RNCl2 with the sulfoxides are almost the same, showing that both are converting the sulfoxide to the same intermediate. A chlorinium ion transfer is suggested.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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