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  • 1
    Electronic Resource
    Electronic Resource
    Kinetics of the oxidation of hypophosphite, deuteriohypophosphite, phosphite and neutralized phenyl phosphonous acid by tris(pyridine-2-carboxylato)manganese(III) in picolinate-picolinic acid buffer medium (2000)
    Springer
    Transition metal chemistry 25 (2000), S. 518-521 
    Details
    ISSN: 1572-901X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Hypophosphite, deuteriohypophosphite, phosphite and neutralized phenyl phosphonous acid are oxidized by tris(pyridine-2-carboxylato)manganese(III) in Na(pic)–picH [where Na(pic) = sodium salt of picolinic acid and picH = picolinic acid] buffer in the 4.63–5.45 pH range. All the reactions appear to follow the same mechanistic pathway in which the substrate initially forms a 1:1 intermediate complex with the oxidant. The complex then breaks down in the rate-determining step to give a free radical intermediate which subsequently reacts with another molecule of oxidant to give the products. A deuterium isotope effect of k H/k D = 4.26 at 313 K, was observed in the oxidation of hypophosphite indicating that proton removal from phosphorus takes place in the rate-determining step. A mechanism consistent with the experimental observations has been proposed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1007076609240
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  • 2
    Electronic Resource
    Electronic Resource
    Kinetics and mechanism of the oxidation of thiosulphate by hexachloroplatinate(IV) (1988)
    Springer
    Transition metal chemistry 13 (1988), S. 155-159 
    Details
    ISSN: 1572-901X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Rate constants for the oxidation of thiosulphate by hexachloroplatinate(IV) have been measured. The kinetics of the oxidation of thiosulphate follow a second-order rate law, first order with respect to thiosulphate and first order with respect to platinum(IV). The influence of pH is small. The rates are found to depend on the nature and concentration of the cations and follow the order: Cs+〉Rb+〉K+〉Na+〉Li+. The activation parameters calculated from the temperature studies are: ΔH
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01087810
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  • 3
    Electronic Resource
    Electronic Resource
    Oxidative behaviour and relative reactivities of α,β-unsaturated compounds towards bis(dihydrogentellurato)cuprate(III) and -argentate(III) in alkaline medium (1998)
    Springer
    Transition metal chemistry 23 (1998), S. 169-173 
    Details
    ISSN: 1572-901X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The kinetics of oxidation of three alpha beta-unsaturated compounds, CH2CHX (X=CN, CONH2 and CO2-) by bis(dihydrogentellurato)metallate(III) ions ([MIII-(H2TeO6)2]5-, M=Cu or Ag) have been studied in an alkaline medium. The reactions take place according to the rate expression: The k3 values are 2.42*10-2, 1.67*10-2 and 1.10*10-2mol6dm-2s-1 for oxidations of the respective substrate by the copper(III) complex and 1.49*10-2, 1.07*10-2 and 0.80*10-2mol6dm-2s-1, respectively, in the oxidations by silver(III), all at 303K. [CuIII(H2TeO6)2]5- reacts faster than the corresponding reactions with [AgIII(H2TeO6)2]5-. The oxidation rates follow the order: CN CONH2CO2-. The oxidations of the substrates by [CuIII(H2TeO6)2]5- take place by an outer-sphere mechanism, unlike [AgIII-(H2TeO6)2]5-, which reacts by an inner-sphere mechanism. The substrates are oxidized to diols under kinetic control and a tentative reaction mechanism leading to the formation of oxidation products is suggested. The activation parameters of the reactions have been evaluated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006955312114
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  • 4
    Electronic Resource
    Electronic Resource
    Kinetics and mechanism of the oxidation of neutralized α-hydroxy acids by tris(pyridine-2-carboxylato)manganese(III) (1999)
    Springer
    Transition metal chemistry 24 (1999), S. 268-273 
    Details
    ISSN: 1572-901X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The kinetics of oxidation of the neutralized α-hydroxy acids: lactic, α-hydroxyisobutyric, mandelic, benzilic and atrolactic acids by tris(pyridine-2-carboxylato)manganese(III) have been studied. The reactions were carried out in a Na(pic)-picH [Na(pic) = sodium salt of pyridine-2-carboxylic acid and picH = pyridine-2-carboxylic acid] buffer medium in the 4.89–6.10pH range. The oxidation rate was found to be independent of pH, and rate follows the order: benzilate 〉 mandelate 〉atrolactate〉lactate 〉 α-hydroxy isobutyrate. The oxidation products are MeCHO, Me2CO, PhCHO, Ph2CO and PhCOMe for the respective reactions. A mechanism is proposed involving intermediate formation of hepta-coordinated MnIII complexes in a fast step. The complexes then decompose to give free radicals and MnII in the rate determining step. The free radicals subsequently react with another molecule of the MnIII species to give the respective carbonyl compounds in a fast step.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006989810426
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  • 5
    Electronic Resource
    Electronic Resource
    Kinetics of oxidation of sulphite by hexachloroplatinate(IV) in acidic solution (1987)
    Springer
    Transition metal chemistry 12 (1987), S. 417-420 
    Details
    ISSN: 1572-901X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The kinetics of the oxidation of sulphite by hexachloroplatinate(IV) has been studied over wide range of experimental conditions. The reaction is first-order in substrate and in platinum(IV). The rate decreases with the increase in acidity. The effect of salt and of changing dielectric constants on the reaction rate have been studied. Values of ΔH
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01171652
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  • 6
    Electronic Resource
    Electronic Resource
    Kinetics and mechanism of the oxidation of alkyl and aryl methyl ketones by permanganate ion in aqueous ethanoic acid (1998)
    Springer
    Transition metal chemistry 23 (1998), S. 577-582 
    Details
    ISSN: 1572-901X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The kinetics of electron-transfer reactions between permanganate ion and ethyl and aryl methyl ketones have been studied in aqueous MeCO2H acid medium in the presence of HClO4 at different temperatures. For ethyl methyl ketone and XC6H4COMe (X = p-Cl, p-Br or p-NO2) the reaction obeys the rate law −d[MnO4−]/dt = (kKe[H+][MnO4−][RCO Me])/(1 + Ke[H+][RCOMe]).␣But the oxidations of XC6H4COMe (X = p-Me and p-OMe)␣follow the rate equation −d[MnO4−]/dt = k3[H+][MnO4−][RCOMe]. The reaction involves a fast pre-equilibrium with intermediate formation of a permanganate ester before the two-electron transfer, rate-determining, step. A number of thermodynamic parameters have been evaluated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006980502784
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  • 7
    Electronic Resource
    Electronic Resource
    Physicochemical studies on Iron(III)-atrolactate and Iron(III)-α-hydroxyisobutyrate chelates (1971)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 384 (1971), S. 280-286 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Es wurden gelbe Fe III-Komplexe mit Atromilchsäure sowie α-Hydroxy-isobuttersäure isoliert und spektrophotometrisch charakterisiert. Die Gleich-gewichtskonstanten und thermodynamischen Parameter (- ΔG, ΔH, ΔS) der Komplexe wurden ermittelt.
    Notes: Atrolactic as well as α-hydroxyisobutyric acids form yellow 1:1- complexes with iron(III) which could be isolated. The nature of the complexes has been studied spec-trophotometrically. The equilibrium constants as well as the thermodynamic parameters, e.g. - ΔG, ΔH, ΔS, of the complexes have been evaluated.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19713840313
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  • 8
    Electronic Resource
    Electronic Resource
    Kinetics and mechanism of the oxidation of glycolaldehyde by tetrachloroaurate(III) (1998)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 30 (1998), S. 613-619 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the reaction between glycolaldehyde (GA) and tetrachloroaurate(III) in acetic acid-sodium acetate buffer has been studied. The reaction is first-order with respect to [AuIII] as well as [GA]. Both H+ and Cl- ions retard the rate of reaction. AuCl4-, AuCl3(OH2), and AuCl3(OH)- are the reactive species of gold(III) with gradually increasing reactivity. A reaction mechanism involving two-electron transfer rate determining steps has been proposed. © 1998 John Wiley & Sons, Inc. Int J Chem Kinet: 30: 613-619, 1998
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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