Reaction to Halogens and Interhalogens with 4-Halo-1,1,2-trifluorobut-1- enes: Rearrangement of 3-Membered Halonium to 5-Membered Trifluorotetramethylene Halonium Ion Intermediates and Comparison of Open- Chloronium Fluorosubstituted Ions to Flurocarboca

摘要

In this paper we investigate the influence that a 4-halosubstituent has on formation of three-membered halonium ions and their rearrangement to five-membered ring intermediates when chloronium, bromonium and iodonium ions from alkenes 1, 2 and 3 are formed in aprotic solvent (Scheme 1). We also compare the open-ion chloronium ions with the open-carbocations from addition of a proton to terminal fluorosubstituted alkenes.