A KINETIC STUDY OF THE PHOTOCHEMICAL ADDITION OF PHENANTHRENEQUINONE TO OLEFINS.
Abstract
A detailed kinetic study of the photochemical addition of phenanthrenequinone to olefins has been made using an apparatus which permits the simultaneous measurement of quantum yields and the rate of disappearance of the activated species. The mechanism formulated from the kinetic data predicts the observed linear relationship between the log ((Io/I) - 1) and time (Io = incident light intensity, I = transmitted light intensity). Further, the quantum yield is independent of olefin concentration but is dependent on the nature of the olefin as well as on the initial ratio of cis-trans isomers. Additional kinetic results include the absence of quenching by oxygen at high olefin-phenanthrenequinone ratios, a small secondary deuterium isotope effect in the rate of addition, and the lack of quenching by the adduct and by two known triplet quenchers. In the stilbene system sensitized cis-trans isomerization occurs with the eventual attainment of an equilibrium cis-trans ratio. Both isomers give the identical adduct. Intersystem crossing of excited quinone appears to be very efficient, but the rates of triplet energy transfer to the cis and trans stilbenes are not equal. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1965
- Accession Number
- AD0629478
Entities
People
- James J. Bohning
Organizations
- Northeastern University