Homogeneous catalysis of deuterium transfer by potassium hydroxide and potassium methoxide D2–H2O and D2–CH3OH exchange

1977 ◽  
Vol 55 (20) ◽  
pp. 3515-3526 ◽  
Author(s):  
Graeme G. Strathdee ◽  
David M. Garner ◽  
Russell M. Given
Keyword(s):  
Potassium Hydroxide ◽  
Isotope Effects ◽  
Kinetic Isotope Effects ◽  
Reaction Rates ◽  
Potassium Methoxide ◽  
Kinetic Isotope ◽  
Rapid Exchange ◽  
Encounter Complex ◽  
Solvent Activity ◽  
Rate Of Activation

The kinetics and mechanism of exchange of deuterium between D2 and water and between D2 and methanol, catalyzed respectively by concentrated potassium hydroxide and potassium methoxide, has been studied between 348 and 398 K. In the D2–KOH–H2O case, the transfer of deuterium was found to be controlled by the rate of activation of the D2 molecule by OH−. Rapid exchange of D+ with the aqueous solution followed. From the D2–KOCH3–CH3OH studies, it was concluded that deuterium exchange depended upon the rates of both D2 activation by methoxide and interaction of the solvent with the transition, or encounter, complex. The dependence of second-order rate constants on solvent activity for both systems was determined by normalization of the exchange reaction rates to unit reagent activity. Analysis of the kinetic isotope effects for each system suggested that their increase with base concentration or temperature was due to solvation effects.

ChemInform Abstract: 1,3-Hydron Transfer in Some 5- or 7-Substituted 1-Methylindenes. Reaction Rates and Kinetic Isotope Effects.

ChemInform ◽  
2010 ◽  
Vol 29 (43) ◽  
pp. no-no
Author(s):  
M. AUNE ◽  
R. DANIELSSON ◽  
A. HUSSENIUS ◽  
P. RYBERG ◽  
A. G. KRISTJANSDOTTIR ◽  
...  
Keyword(s):  
Isotope Effects ◽  
Kinetic Isotope Effects ◽  
Reaction Rates ◽  
Kinetic Isotope ◽  
Substituted 1

Kinetics and mechanism of the oxidation of alcohols by ferrate ion

1993 ◽  
Vol 71 (9) ◽  
pp. 1394-1400 ◽  
Author(s):  
Donald G. Lee ◽  
Huifa Gai
Keyword(s):  
Transition Metal Oxides ◽  
Isotope Effects ◽  
Substituent Effects ◽  
Kinetic Isotope Effects ◽  
Reaction Rates ◽  
Radical Intermediates ◽  
Kinetic Isotope ◽  
Oxidation Of Alcohols ◽  
Aliphatic Ether ◽  
High Valent

A kinetic study of the reduction of ferrate ion under basic conditions has been completed. The observation that a typical aliphatic ether, tetrahydrofuran, is oxidized at a rate comparable to that of aliphatic alcohols, such as cyclopentanol, indicates that the reaction between ferrate and alcohols is likely initiated by attack of the oxidant at an α-C—H bond, a conclusion that is consistent with the occurrence of primary deuterium kinetic isotope effects (2.8–4.3 at 25 °C) when α-hydrogens are replaced by deuterium. Because only acyclic products are obtained from the oxidation of cyclobutanol by ferrate, it may be concluded that free radical intermediates are involved in the reaction. The insensitivity of the reaction rates to substituent effects during the oxidation of substituted mandelic acids indicates that substantial charges are not built up in the transition state. All of these observations are most readily accommodated by a mechanism in which the reaction is initiated by a 2 + 2 addition of an Fe=O bond to the α-C—H of an alcohol to give an organometallic intermediate that subsequently decomposes by homolytic cleavage of the resulting C—Fe bond. Comparisons are made with the reactions between alcohols and other high-valent transition metal oxides.

scholarly journals 1,3-Hydron Transfer in Some 5- or 7-Substituted 1-Methylindenes. Reaction Rates and Kinetic Isotope Effects.

1998 ◽  
Vol 52 ◽  
pp. 911-920 ◽  
Author(s):  
Marie Aune ◽  
Rolf Danielsson ◽  
Anita Hussénius ◽  
Per Ryberg ◽  
Ása Guorún Kristjánsdóttir ◽  
...  
Keyword(s):  
Isotope Effects ◽  
Kinetic Isotope Effects ◽  
Reaction Rates ◽  
Kinetic Isotope ◽  
Substituted 1

scholarly journals Kinetic isotope effects in the gas phase reactions of OH and Cl with CH<sub>3</sub>Cl, CD<sub>3</sub>Cl, and <sup>13</sup>CH<sub>3</sub>Cl

2005 ◽  
Vol 5 (3) ◽  
pp. 3873-3898 ◽  
Author(s):  
A. A. Gola ◽  
B. D’Anna ◽  
K. L. Feilberg ◽  
S. R. Sellevåg ◽  
L. Bache-Andreassen ◽  
...  
Keyword(s):  
Cross Sections ◽  
Relative Rate ◽  
Isotope Effects ◽  
Kinetic Isotope Effects ◽  
Reaction Rates ◽  
Oh Radicals ◽  
Gas Phase Reactions ◽  
Global Emission ◽  
Kinetic Isotope ◽  
Fitting Method

Abstract. The kinetic isotope effects in the reactions of CH3Cl, 13CH3Cl and CD3Cl with OH radicals and Cl atoms were studied in relative rate experiments at 298±2K and 1013±10mbar. The reactions were carried out in a smog chamber using long path FTIR detection and the spectroscopic data analyzed employing a non-linear least squares spectral fitting method using measured high-resolution infrared spectra as well as absorption cross sections from the HITRAN database. The reaction rates of 13CH3Cl and CD3Cl with OH and Cl were determined relative to CH3Cl as: kOH + CH3Cl/kOH + 13CH3Cl=1.059±0.008, kOH + CH3Cl/kOH + CD3Cl=3.9±0.4, kCl + CH3Cl/kCl + 13CH3Cl=1.070±0.010 and kCl + CH3Cl/kCl + CD3Cl=4.91±0.07. The uncertainties given are 2σ from the statistical analyses and do not include possible systematic errors. The unusually large 13C kinetic isotope effect in the OH reaction of CH3Cl has important implications for the global emission inventory of CH3Cl.

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