PHOTOLYSIS OF AZOISOPROPANE

Abstract

The photolysis of azoisopropane has been reinvestigated in an attempt to obtain a better understanding of the discrepancies found between the behavior of sec-propyl radicals produced from this source (1) and other sources under similar experimental conditions.Analytical difficulties encountered in an earlier investigation (1) were avoided through the extensive use of gas chromatography.It was found necessary to include an internal conversion reaction among the primary processes to explain the observed phenomena. A rough estimate of Einternal conversion − Edissociation = (1.99 ± 0.72) kcal/mole has been deduced. This is believed to be the first observation of Einternal conversion > Edissociation. An explanation of this observation remains a matter of conjecture though a tentative suggestion is offered.The data also leads to results in agreement with those found for other azo compounds and in agreement with the rates of reactions of sec-propyl radicals obtained from other sources under similar conditions.