ISSN:
0947-3440
Keywords:
Bond cleavage, C-C, kinetics of
;
Allyl radicals, stability of
;
Calculations, molecular mechanics
;
Enthalpies of formation
;
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The title radicals were generated by thermal decomposition of (E,E)-meso- and (E,E)-(±)-5,6-di-tert-butyl-2,2,9,9-tetramethyl-3,7-decadiene (4a, b), (E)-5-(1,1-dimethylethyl)-2,2,6-trimethyl-6-phenyl-3-heptene (6), and (E)-5-(diphenyl-methyl)-2,2,6,6-tetramethyl-3-heptene (7). The activation parameters of these reactions were calculated from the rate constants which were followed over a 40°C temperature range. The enthalpies of formation of 4a, b were determined from the enthalpies of combustion and enthalpies of vaporization, those of 6 and 7 by MM2 calculation. From these data and their comparison with those of comparable saturated hydrocarbons of similar strain the radical stabilization enthalpy of the title radical RSE = 11.4 ± 1.5 kcal/mol was determined, which is in good agreement with results obtained from other model compounds (12.6 kcal/mol) previously.
Additional Material:
8 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jlac.199519950371
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