The thermal decomposition of 1-ethoxyethyl chloride and the reverse combination

1967 ◽  
Vol 20 (8) ◽  
pp. 1553 ◽  
Author(s):  
RL Failes ◽  
VR Stimson
Keyword(s):  
Thermal Decomposition ◽  
Transition State ◽  
Hydrogen Chloride ◽  
Ethyl Ether ◽  
Reverse Reaction ◽  
Kcal Mole ◽  
First Order ◽  
Polar Transition

1-Ethoxyethyl chloride decomposes cleanly at 164-221� into vinyl ethyl ether and hydrogen chloride in a first-order manner with k1 = 1010.52exp(-30300/RT) sec-1 (1) The equilibrium of the system at 128-221� approached from either direction at various pressures is well represented by (Kp in atmospheres) 1.987 In Kp = 31.1 � 0.9-(16500�500)/T (2) and this leads to ΔH�f,298(g) = -71.9 kcal mole-1 for 1-ethoxyethyl chloride. Combination of (1) and (2) gives k2 = 108.7exp(-14700/RT) sec-1 ml mole-1 for the reverse reaction and rate measurements verify this. The reactions are molecular, and relative rates indicate a polar transition state.

The thermal decomposition of 2-chloroethanol

1976 ◽  
Vol 29 (3) ◽  
pp. 609 ◽  
Author(s):  
DC Skingle ◽  
VR Stimson
Keyword(s):  
Thermal Decomposition ◽  
Hydrogen Chloride ◽  
Ethyl Chloride ◽  
First Order ◽  
Order Rate ◽  
Polar Transition

2-Chloroethanol decomposes at 430-496� into acetaldehyde and hydrogen chloride with first-order rate given by: k1 = 1012.8�1 exp(-229700 � 4000/8.314T) s-l The rate is slightly less than that for ethyl chloride. That acetaldehyde is the product shows that a 1-2 shift of hydrogen has taken place and this is indicative of a polar transition state.The acetaldehyde subsequently decomposes to methane and this decomposition is catalysed by the hydrogen chloride produced.

Catalysis by hydrogen halides in the gas phase. XI. Tertiary butyl ethyl ether and hydrogen chloride

1966 ◽  
Vol 19 (3) ◽  
pp. 401 ◽  
Author(s):  
VR Stimson ◽  
EJ Watson
Keyword(s):  
Gas Phase ◽  
Hydrogen Chloride ◽  
Ethyl Ether ◽  
Arrhenius Equation ◽  
Hydrogen Halide ◽  
Hydrogen Halides ◽  
Tertiary Butyl ◽  
First Order ◽  
Mechanism Of The Reaction ◽  
Kinetic Form

Hydrogen chloride catalyses the decomposition of t-butyl ethyl ether at 320-428�. Isobutene is quantitatively the product and the kinetic form is first order in the ether and in hydrogen chloride. The Arrhenius equation:��������� k, = 1012'16exp( -30,60O/RT) (sec-l ml mole-=) is followed. The mechanism of the reaction seems similar to those of other hydrogen halide catalysed decompositions of ethers and alcohols.

FREE RADICALS BY MASS SPECTROMETRY: XXXV. THE HEAT OF FORMATION OF ALLYL RADICAL FROM BIALLYL PYROLYSIS

1966 ◽  
Vol 44 (18) ◽  
pp. 2211-2217 ◽  
Author(s):  
J. B. Homer ◽  
F. P. Lossing
Keyword(s):  
Mass Spectrometry ◽  
Activation Energy ◽  
Thermal Decomposition ◽  
Total Pressure ◽  
Heat Of Formation ◽  
Kcal Mole ◽  
Allyl Radical ◽  
First Order ◽  
Secondary Reactions ◽  
Gas Pressures

The thermal decomposition of biallyl has been investigated from 977 – 1 070 °K at helium carrier gas pressures of 10–50 Torr. Under these conditions the rate of central C—C bond fission to give two allyl radicals can be measured without interference from secondary reactions. The reaction at the pressures employed is first order with respect to biallyl, but between first and second order in the total pressure. The temperature dependence of the rate constants, extrapolated to infinite pressure, and corrected to 298 °K, gives an activation energy of 45.7 kcal/mole for the reaction, corresponding to ΔHf(allyl) = 33.0 kcal/mole.

The pyrolysis of alkyl chlorides on the surface of Pyrex glass

1964 ◽  
Vol 17 (11) ◽  
pp. 1217 ◽  
Author(s):  
JS Shapiro ◽  
ES Swinbourne ◽  
BC Young
Keyword(s):  
Hydrogen Chloride ◽  
Heterogeneous Reaction ◽  
Initial Pressure ◽  
Pyrex Glass ◽  
Kcal Mole ◽  
Arrhenius Activation Energy ◽  
First Order ◽  
Determining Factor ◽  
Chlorine Bond ◽  
Selection Of

A study has been made of the surface-catalysed dehydrochlorination of a selection of gaseous chlorinated hydrocarbons on Pyrex glass. For primary chlorides at 413� the rate sequence: ethyl<n-propyl<isobutyl<neopentyl was observed for 200 mm initial pressure of reagent. Ethyl chloride decomposes at 400-450� according to a first-order law, and the overall Arrhenius activation energy for the heterogeneous reaction is 24.1 kcal/mole; the rate is slightly depressed by the addition of propene and slightly enhanced by hydrogen chloride. Catalysis by hydrogen chloride was observed to be much more marked in the case of isopropyl chloride decomposition at 190-250�, but reproducible behaviour for this reaction was not readily attained. The catalytic action of Pyrex glass is accounted for by the polar surface assisting in the separation of charges within the reacting molecule, emphasis being placed upon the polarization of the carbon-chlorine bond as the important rate-determining factor.

Mechanism of thermal decomposition of dibenzhydryl oxalates

1967 ◽  
Vol 45 (24) ◽  
pp. 3035-3043 ◽  
Author(s):  
J. Warkentin ◽  
D. M. Singleton
Keyword(s):  
Thermal Decomposition ◽  
Transition State ◽  
High Temperatures ◽  
Diphenyl Ether ◽  
Isotope Effects ◽  
Slow Step ◽  
Radical Process ◽  
First Order ◽  
Mechanism Of Thermal Decomposition ◽  
O Isotope

Dibenzhydryl oxalate and several of its para-substituted analogs were thermally decomposed in diphenylmethane, diphenyl ether, and in α-chloronaphthalene solution. Evolution of gas (mainly CO2) was approximately first order, both rate and stoichiometry being poorly reproducible. Rates are correlated with σ+-substituent parameters, with ρ = −1.6 at 230.2°. The 13C/12C and 18O/16O isotope effects involved in CO2 formation were measured. It is concluded that thermolysis is a radical process with considerable polar character at the transition state and that the slow step involves concerted formation of one CO2 molecule, a diarylmethyl radical, and a carbodiarylmethoxy radical. The fate of the latter is primarily decarboxylation, but there is some decarbonylation and some trapping by diarylmethyl radicals. Tetraaryl ethane and CO2 are major products, the yield of the latter approaching 2 moles at high temperatures.

scholarly journals The dissociation energy of the C-N bond in benzylamine

1949 ◽  
Vol 198 (1053) ◽  
pp. 285-292 ◽  
Keyword(s):  
Activation Energy ◽  
Thermal Decomposition ◽  
Dissociation Energy ◽  
Heat Of Formation ◽  
Molar Ratio ◽  
Kcal Mole ◽  
First Order ◽  
First Order Kinetics ◽  
Permanent Gases ◽  
Kinetics Of

The kinetics of the thermal decomposition of benzylamine were studied by a flow method using toluene as a carrier gas. The decomposition produced NH 3 and dibenzyl in a molar ratio of 1:1, and small quantities of permanent gases consisting mainly of H 2 . Over a temperature range of 150° (650 to 800° C) the process was found to be a homogeneous gas reaction, following first-order kinetics, the rate constant being expressed by k = 6 x 10 12 exp (59,000/ RT ) sec. -1 . It was concluded, therefore, that the mechanism of the decomposition could be represented by the following equations: C 6 H 5 . CH 2 . NH 2 → C 6 H 5 . CH 2 • + NH 2 •, C 6 H 5 . CH 3 + NH 2 •→ C 6 H 5 . CH 2 • + NH 3 , 2C 6 H 5 . CH 2 •→ dibenzyl, and the experimentally determined activation energy of 59 ± 4 kcal./mole is equal to the dissociation energy of the C-N bond in benzylamine. Using the available thermochemical data we calculated on this basis the heat of formation of the NH 2 radical as 35.5 kcal./mole, in a fair agreement with the result obtained by the study of the pyrolysis of hydrazine. A review of the reactions of the NH 2 radicals is given.

THE THERMAL DECOMPOSITION OF METHYL HYDROPEROXIDE

1965 ◽  
Vol 43 (8) ◽  
pp. 2236-2242 ◽  
Author(s):  
Alexander D. Kirk
Keyword(s):  
Activation Energy ◽  
Thermal Decomposition ◽  
Gas Phase ◽  
Rate Constants ◽  
Dimethyl Phthalate ◽  
Kcal Mole ◽  
First Order ◽  
Methyl Hydroperoxide ◽  
Expected Values ◽  
Homogeneous Decomposition

The thermal decomposition of methyl hydroperoxide has been studied in solution and in the gas phase. The decomposition was found to be partly heterogeneous in solution in dimethyl phthalate and no reliable rate constants were obtained. Use of the toluene carrier method for the gas phase work enabled measurement of the rate constant for the homogeneous decomposition. The first order rate constants obtained range from 0.19 s−1 at 292 °C to 1.5 s−1 at 378 °C, leading to log A, 11± 2, and activation energy, 32 ± 5 kcal/mole. These results are compared with the expected values of log A, 13–14, and activation energy, 42 kcal/mole. The significance of these findings is discussed.

The thermal decomposition of trimethylacetyl bromide

1970 ◽  
Vol 23 (3) ◽  
pp. 525 ◽  
Author(s):  
BS Lennon ◽  
VR Stimson
Keyword(s):  
Thermal Decomposition ◽  
Carbon Monoxide ◽  
Hydrogen Bromide ◽  
Transition States ◽  
Volume Ratio ◽  
Reaction Vessel ◽  
Chain Mechanism ◽  
Radical Chain ◽  
First Order ◽  
Polar Transition

Trimethylacetyl bromide decomposes at 298-364� into isobutene, carbon monoxide, and hydrogen bromide in a first-order manner with rate given by k1 = 138 x 1014exp(-48920/RT) sec-1 The rate is unaffected by addition of the products or of inhibitors, or by increase of the surface/volume ratio of the reaction vessel. The likely radical chain mechanism is considered and rejected. The reaction is believed to be a molecular one, and possible cyclic and polar transition states are discussed.

Acetoxylation by aryliodoso acetates. II. Kinetics of the reaction of phenyliodoso acetate with aceto-p-toluidide

1958 ◽  
Vol 11 (1) ◽  
pp. 34
Author(s):  
WD Johnson ◽  
NV Riggs
Keyword(s):  
Acetic Acid ◽  
Acetic Anhydride ◽  
Transition State ◽  
Arrhenius Equation ◽  
First Order ◽  
Temperature Range ◽  
Polar Transition ◽  
Kinetics Of

The reaction of phenyliodoso acetate and aceto-p-toluidide in acetic acid is first order in each reactant and measured rates fit the Arrhenius equation in the temperature range 15-45 �C. Addition of water to the solvent markedly accelerates the reaction, whereas addition of benzene lowers the rate and acetic anhydride has little effect. A polar transition state is indicated.

Thermal decomposition of di-tert-butyl peroxide at high pressure

1968 ◽  
Vol 46 (16) ◽  
pp. 2721-2724 ◽  
Author(s):  
D. H. Shaw ◽  
H. O. Pritchard
Keyword(s):  
Carbon Dioxide ◽  
Thermal Decomposition ◽  
High Pressure ◽  
Shock Tube ◽  
Total Pressure ◽  
Order Rate Constant ◽  
Kcal Mole ◽  
First Order ◽  
Tert Butyl ◽  
Butyl Peroxide

The thermal decomposition of di-tert-butyl peroxide has been studied in the presence of carbon dioxide at total pressures from 0.05 to 15 atm and temperatures from 90–130 °C. The first-order rate constant for the decomposition is independent of total pressure in this range, with Arrhenius parameters E = 37.8 ± 0.3 kcal/mole and log A(s−1) = 15.8+0.2. A reevaluation of previous data on this reaction leads us to recommend E = 37.78 ± 0.06 kcal/mole and log A(s−1) = 15.80 ± 0.03 over the temperature range 90–350 °C; extension of this range to higher temperatures using a shock tube would be worthwhile.

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