Intramolecular Isotope Effects for the Study of Reactions with MassTransfer Limitations

Abstract

The research presented provides a method to use the comparison of intermolecular isotope effects vs. the intramolecular isotope effects for the study of reactions in which study of the rate limiting step is ambiguous due to interfering mass transfer effects. The oxidation of unfunctionalized hydrocarbons at mild conditions developed by Sir Derek Barton, the Gif reaction is the model used. The history is provided to demonstrate the relevance of using this model as one which could show the usefulness of this method. Evidence has been provided and used to theorize that the rate limiting step of the reaction may be diffusion of the reactants, not a chemical change. Starting materials were made which would allow for the measurement for both the intermolecular and intramolecular KIE and those values were compared. The results show that there is little difference between the intermolecular and intramolecular KIE, therefore the reaction is not diffusion controlled.