New electronegativity scale for the correlation of heats of formation. 3. Bond dissociation energy of X-R bonds and the heat of formation of the isopropyl radical

1989 ◽  
Vol 93 (8) ◽  
pp. 3304-3306 ◽  
Author(s):  
Yu Ran Luo ◽  
Sidney W. Benson
Keyword(s):  
Bond Dissociation Energy ◽  
Dissociation Energy ◽  
Heat Of Formation ◽  
Heats Of Formation ◽  
Bond Dissociation

Determination of the heat of formation of trimethylindium and calculation of the mean In—CH3 bond dissociation energy

1968 ◽  
Vol 46 (10) ◽  
pp. 1633-1634 ◽  
Author(s):  
W. D. Clark ◽  
S. J. W. Price
Keyword(s):  
Bond Dissociation Energy ◽  
Dissociation Energy ◽  
Chloroform Solution ◽  
Kinetic Studies ◽  
Heat Of Formation ◽  
Enthalpy Of Reaction ◽  
Kcal Mole ◽  
Bond Dissociation ◽  
The Mean

The enthalpy of reaction of In(CH3)3,c with a chloroform solution of bromine is −162.5 kcal mole−1. With this value ΔHf0298[In(CH3)3,c] = 29.5 kcal mole−1 and ΔHf0298[In(CH3)3,g] = 41.1 kcal mole−1. Combining the latter with ΔHf0298[CH3,g] = 33.2 kcal mole−1 and ΔHf0298[In,g] = 58.2 kcal mole−1 then gives E(In—CH3) = 38.9 kcal mole−1. From previous kinetic studies D[(CH3)2In—CH3] + D[In—CH3] = 87.9 kcal mole−1. Hence D[CH3In—CH3] = 28.8 kcal mole−1.

The CH 2 : CH.CH 2 —CH 3 bond dissociation energy and the heat of formation of the allyl radical

1950 ◽  
Vol 202 (1069) ◽  
pp. 263-276 ◽  
Keyword(s):  
Bond Dissociation Energy ◽  
Dissociation Energy ◽  
Heat Of Formation ◽  
Methyl Radicals ◽  
Kcal Mole ◽  
Allyl Radical ◽  
First Order ◽  
Bond Dissociation ◽  
Benzyl Radicals ◽  
Thermal Stability Of

The pyrolysis of butene-1 was investigated by a flow technique, toluene being used as a carrier gas. It was found that butene-1 decomposed into allyl and methyl radicals according to the equation CH 2 : CH.CH 2 — CH 3 → CH 2 : CH.CH 2 + CH 3 . Methyl radicals were removed by reaction with toluene giving methane and benzyl radicals. The rate of the initial decomposition was measured by the rate of formation of methane. The decomposition was found to be a homogeneous first order gas reaction. The activation energy was calculated at 61.5 kcal./mole and it was identified with the CH 2 : CH.CH 2 — CH 3 bond dissociation energy. Taking D (CH 2 : CH.CH 2 —CH 3 ) at 61.5 kcal./mole we calculated from thermochemical data D (CH 2 : CH.CH 2 —H) at 76.5 kcal./mole and the heat of formation of allyl radical at + 30 kcal./mole. The fate of allyl radicals is discussed and the thermal stability of these is compared with that of benzyl radicals.

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