γ-Radiosensitized isomerization of gaseous butenes and methylbutenes

Abstract

We have studied the isomerization of butenes and methylbutenes by noble gas-sensitized radiolysis. The isomerization of isobutene to but-2-ene is more efficient in the presence of xenon than in the presence of krypton or argon. The isomerization of but-1-ene into isobutene has a low radiolytic yield and occurs only in the presence of small quantities of dimethylamine. These observations are in agreement with the isomerization of the excited parent ion.In the methylbutene systems, whatever the sensitizing agent, isomerization occurs with a high radiolytic yield. Thus, a chain mechanism is needed to explain the results. The addition of dimethylamine has a reverse effect relative to that observed in but-1-ene. It is concluded that the mechanism invoked for the butene systems is not adequate for explaining the isomerization observed in the methylbutene systems.