Kinetic Isotope Effects in H and D Abstraction Reactions from Alcohols by D Atoms in Aqueous Solution

1998 ◽  
Vol 102 (38) ◽  
pp. 7462-7469 ◽  
Author(s):  
Annett M. Lossack ◽  
Emil Roduner ◽  
David M. Bartels
Keyword(s):  
Aqueous Solution ◽  
Isotope Effects ◽  
Kinetic Isotope Effects ◽  
Kinetic Isotope

Radiation-induced Oxidation of 2-Propanol by Nitrous Oxide in Alkaline Aqueous Solution

1972 ◽  
Vol 50 (11) ◽  
pp. 1751-1756 ◽  
Author(s):  
C. E. Burchill ◽  
G. P. Wollner
Keyword(s):  
Aqueous Solution ◽  
Rate Constant ◽  
Isotope Effects ◽  
Kinetic Isotope Effects ◽  
Chain Mechanism ◽  
Radical Chain ◽  
Kinetic Isotope ◽  
Alkaline Aqueous Solution ◽  
Radiation Induced ◽  
Solution Proceeds

The radiation-induced oxidation of 2-propanol to acetone by N2O in alkaline aqueous solution proceeds via a free radical chain mechanism independent of pH above 12.5. The results are explained by abstraction of H from 2-propanol by O− at both the α and β positions (85% α attack). Chain propagation is by reaction of the α radical anion, (CH3)2ĊO−, with N2O with a rate constant of (3.8 ± 0.4) × 104 M−1 s−1 and by reaction of the β radical, ĊH2(CH3)CHOH, with 2-propanol to give the α radical with a rate constant of 430 ± 30 M−1 s−1.The conclusions are supported by the demonstration of kinetic isotope effects for selectively deuterated alcohols.

Secondary Isotope Effects on the Ionization of 2-Nitropropane

1974 ◽  
Vol 52 (10) ◽  
pp. 1889-1896 ◽  
Author(s):  
A. J. Kresge ◽  
D. A. Drake ◽  
Y. Chiang
Keyword(s):  
Aqueous Solution ◽  
Isotope Effect ◽  
Kinetic Isotope Effect ◽  
Isotope Effects ◽  
Kinetic Isotope Effects ◽  
Acid Dissociation ◽  
Methyl Groups ◽  
Anomalous Effect ◽  
Hydroxide Ion ◽  
Kinetic Isotope

The equilibrium isotope effect on the acid dissociation of 2-nitropropane in wholly aqueous solution at 25° was found to be KH/KD = 1.23 ± 0.03 for complete deuteration of both methyl groups; the kinetic isotope effect for reaction of the same substrate with hydroxide ion, kH/kD = 1.09 ± 0.01; and the kinetic isotope effect for reaction with tris-(hydroxymethyl)-methylamine, kH/kD = 1.10 ± 0.01; both of the latter also refer to wholly aqueous solution at 25° and are for complete deuteration of both methyl groups. It is shown that the equilibrium isotope effect is largely, and the kinetic isotope effects probably partly, hyper conjugative in origin, thus supporting a hyper conjugative explanation of the anomalous effect of methyl groups on nitroalkane ionization.

The Bimolecular Decay of the α - Hydroxymethylperoxyl Radicals in Aqueous Solution

1978 ◽  
Vol 33 (7) ◽  
pp. 786-788 ◽  
Author(s):  
Eberhard Bothe ◽  
Dietrich Schulte-Frohlinde
Keyword(s):  
Aqueous Solution ◽  
Formic Acid ◽  
Room Temperature ◽  
Isotope Effects ◽  
Kinetic Isotope Effects ◽  
Kinetic Isotope

The bimolecular decay of the hydroxymethylperoxyl radical in aqueous solution (k = 2.1 x 109 M-1s-1) leads mainly (80%) to one molecule of hydrogen peroxid and to two molecules of formic acid. 2 HOCH2OO· → H2O2 + 2 HCOOH Deuterium kinetic isotope effects show that the decay occurs at room temperature via a short lived (τ < 10-4 s) tetroxid.

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