The kinetics and mechanisms of the gas phase pyrolyses of exo-2-norbornyl chloride and cyclopentyl chloride

1979 ◽  
Vol 57 (19) ◽  
pp. 2621-2625 ◽  
Author(s):  
J. L. Holmes ◽  
D. L. McGillivray ◽  
D. Yuan
Keyword(s):  
Gas Phase ◽  
Hydrogen Chloride ◽  
Isotope Effect ◽  
Deuterium Isotope Effect ◽  
Temperature Range ◽  
Elimination Reactions ◽  
Chloride Elimination ◽  
Kinetics Of

The gas phase pyrolyses of exo-2-norbornyl chloride and cyclopentyl chloride were studied in the temperature range 570–670 K. The results obtained show that these compounds behave as typical secondary halides insofar as the kinetics of their hydrogen chloride elimination reactions are concerned. Labelling experiments showed that in the formation of both norbornene and cyclopentene, a cis-1,2 elimination with a deuterium isotope effect of ∼3 was involved. Nortricyclene also was produced from exo-2-norbornyl chloride, via a trans 1,3 elimination; this process is analogous to a fragmentation of the ionized molecule. No gas phase Wagner–Meerwein rearrangement was involved in the formation of either norbornene or nortricyclene.

scholarly journals The influence of crown ethers on the kinetics of E1cB and E2 β-elimination reactions of di(4-nitrophenyl)fluoroethanes with sodium methoxide in methanol

1982 ◽  
Vol 60 (24) ◽  
pp. 3077-3080
Author(s):  
Kenneth T. Leffek ◽  
Grzegorz Schroeder
Keyword(s):  
Isotope Effect ◽  
Crown Ethers ◽  
Rate Constant ◽  
Rate Constants ◽  
Sodium Methoxide ◽  
Activation Parameters ◽  
Deuterium Isotope Effect ◽  
Kinetic Order ◽  
Elimination Reactions ◽  
Kinetics Of

The addition of crown ethers 1,4,7,10,13-pentaoxacyclopentadecane (15C5) and 1,4,7,10,13,16-hexaoxacyclooctadecane (18C6) in quantities equimolar to the base, to β-elimination reactions of 1,1,1-trifluoro-2,2-di(4-nitrophenyl)ethane and 1-fluoro-2,2-di(4-nitrophenyl)ethane promoted by sodium methoxide in methanol, has been investigated. In the E2 reaction of the monofluoro compound, the crown ethers caused no change in the kinetic order and only small changes in the second-order rate constants and activation parameters. The primary deuterium isotope effect was also unaltered by the presence of crown ethers.For the (E1cB)R reaction of the trifluoro compound, no change in kinetic order was found, but slightly larger rate constant changes and an increase in the isotope effect from kH/kD = 1.0 to 1.25 at 25 °C was observed. This is interpreted as an alteration in mechanism from (E1cB)R towards (E1cB)I.

Molecular rearrangements in homogeneous gas-phase elimination reactions. Pyrolysis kinetics of alkyl methanesulphonates

1993 ◽  
Vol 6 (2) ◽  
pp. 85-94 ◽  
Author(s):  
Gabriel Chuchani ◽  
Ignacio Martin ◽  
Rosa M. Dominguez ◽  
Alexandra Rotinov ◽  
Sara Pekerarm ◽  
...  
Keyword(s):  
Gas Phase ◽  
Pyrolysis Kinetics ◽  
Molecular Rearrangements ◽  
Elimination Reactions ◽  
Kinetics Of ◽  
Phase Elimination

scholarly journals The kinetics of the hydrogen chloride oxidation

2013 ◽  
Vol 78 (12) ◽  
pp. 2115-2130 ◽  
Author(s):  
Martinez Gonzalez ◽  
Tanja Vidakovic-Koch ◽  
Rafael Kuwertz ◽  
Ulrich Kunz ◽  
Thomas Turek ◽  
...  
Keyword(s):  
Kinetic Parameters ◽  
Gas Phase ◽  
Hydrogen Chloride ◽  
Reaction Order ◽  
Membrane Electrode ◽  
Polarization Data ◽  
Rate Determining Step ◽  
Electrode Assemblies ◽  
Apparent Kinetic Parameters ◽  
Kinetics Of

Hydrogen chloride (HCl) oxidation has been investigated on technical membrane electrode assemblies in a cyclone flow cell. Influence of Nafion loading, temperature and hydrogen chloride mole fraction in the gas phase has been studied. The apparent kinetic parameters like reaction order with respect to HCl, Tafel slope and activation energy have been determined from polarization data. The apparent kinetic parameters suggest that the recombination of adsorbed Cl intermediate is the rate determining step.

Gas-phase elimination kinetics of selected aliphatic α,β-unsaturated aldehydes catalyzed by hydrogen chloride

2015 ◽  
Vol 28 (4) ◽  
pp. 261-265 ◽  
Author(s):  
Libia L. Julio ◽  
José R. Mora ◽  
Alexis Maldonado ◽  
Gabriel Chuchani
Keyword(s):  
Gas Phase ◽  
Hydrogen Chloride ◽  
Elimination Kinetics ◽  
Unsaturated Aldehydes ◽  
Kinetics Of ◽  
Phase Elimination

The kinetics of proton and deuteron transfer from 4-nitrophenylnitromethane and l-(4-nitrophenyl)-l-nitroethane to 2,7-dimethoxy-l,8-bis(dimethylamino)naphthalene in acetonitrile solvent

1981 ◽  
Vol 59 (21) ◽  
pp. 3034-3038 ◽  
Author(s):  
Kenneth T. Leffek ◽  
Przemyslaw Pruszynski
Keyword(s):  
Isotope Effect ◽  
Reaction Rate ◽  
Significant Contribution ◽  
Reaction Parameters ◽  
Deuterium Isotope Effect ◽  
First Order ◽  
Enthalpy Of Activation ◽  
Deuteron Transfer ◽  
Slow Dissociation ◽  
Kinetics Of

4-Nitrophenylnitromethane reacts with 2,7-dimethoxy-1,8-bis(dimethylamino)naphthalene in acetonitrile in a bimolecular proton transfer, which shows a primary deuterium isotope effect, kH/kD = 12.2 at 25 °C. The large isotope effect on the enthalpy of activation, (ΔHD≠ – ΔHH≠) = 4.6 ± 0.3 kcal mol−1 is consistent with a significant contribution of proton tunnelling to the reaction rate of the protium substrate.The analogous reaction of 1-(4-nitrophenyl)-1-nitroethane with the same base in acetonitrile gives contrasting kinetics and reaction parameters. The reaction is first order, showing no dependence on base concentration. While the isotope effect kH/kD = 9.3 at 25 °C, the enthalpy of activation difference (ΔHD≠ – ΔHH≠) is only 0.5 ± 0.1 kcal mol−1. It is concluded that the 1-(4-nitrophenyl)-1-nitroethane undergoes a slow dissociation, with a very small dissociation constant, followed by a fast association with the base to yield the carbanion ion-pair.

Gas-phase kinetics of elimination reactions of pentane-2,4-dione derivatives

1995 ◽  
Vol 27 (5) ◽  
pp. 517-523 ◽  
Author(s):  
Nouria A. Al-Awadi ◽  
Mohamed H. El-Nagdi ◽  
Tommy Mathew
Keyword(s):  
Gas Phase ◽  
Gas Phase Kinetics ◽  
Elimination Reactions ◽  
Kinetics Of
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