Stereochemical Consequences of Bromine-for-Halogen Substitutions in the Gas Phase

Article abstract of DOI:10.1021/j100412a088

The stereochemistry of translationally excited bromine-for-halogen substitution was studied in gaseous 2(S)- and 2(R)-halopropionyl halides.Net inversion of configuration was observed for 75Br-for-X substitutions with a trend of increasing inversion as the displaced atom was varied in the series, X = F, Cl, Br.A correlation with previous studies on 18F-for-X and 34mCl-for-X substitutions also showed increased inversion with increased mass of the displacing agent.In addition, these recoil atom substitutions showed an apparent independence from the free-energy requirement of reaction.