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A Complication in the thermal reactions of 1,1,2,2‐tetramethylcyclopropane
Author(s) -
Blumstein C.,
Henfling D.,
Sharts C. M.,
O'Neal H. E.
Publication year - 1970
Publication title -
international journal of chemical kinetics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.341
H-Index - 68
eISSN - 1097-4601
pISSN - 0538-8066
DOI - 10.1002/kin.550020102
Subject(s) - chemistry , isomerization , arrhenius equation , thermal decomposition , activation energy , kinetics , decomposition , transition state theory , thermodynamics , gas phase , reaction mechanism , transition state , chemical kinetics , photochemistry , computational chemistry , reaction rate constant , organic chemistry , catalysis , physics , quantum mechanics
Reinvestigation of the gas phase thermal reaction of 1,1,2,2‐tetramethylcyclopropane (699‐759°K) gave for the unimolecular disappearance of reactant, k (TMC) = 10 15.27–63.93/θ sec −1 , in good agreement with the original results of Frey and Marshall. However, evidence for a high activation energy ( E = 79 ± 5 kcal/mole), competitive unimolecular decomposition to 2,3‐dimethyl‐1 and ‐2‐butenes was also obtained. It is proposed that the serious discrepancy noted [1] between the experimentally observed Arrhenius parameters for the overall reaction kinetics, and those predicted by transition state calculations assuming a biradical mechanism for the isomerization reactions (previously believed to be the only primary reaction mode) can be explained in terms of the increasing importance of the decomposition reactions at higher reaction temperatures.