Free-Radical and Anion Intermediates in the Reactions of 5-Halo-2-norbornenes and 3-Halonotricyclenes with (Trimethyltin)sodium

Article abstract of DOI:10.1021/jo00319a002

The reaction of (trimethyltin)sodium with exo-5-chloro- and 5-bromo-2-norbornenes, endo-5-bromo-2-norbornene, and 3-bromo- and 3-iodonortricyclene in tetrahydrofuran has been examined.Use of dicyclohexylphosphine as a trap for intermediate radicals by hydrogen atom transfer showed that the bromides and chloride reacted predominantly by way of free-radical intermediates and by geminate reactions.The geminate products showed complete equilibration of the intermediate radicals. 3-Iodonorbornene reacted predominantly by an anionic intermediate mechanism as shown by trapping of the anions with tert-butylamine.