Electron‐impact‐induced rearrangements of organic ions: IV—Hydrogen and carbon scrambling in [t‐C3H8N]+ metastable ions

Independent loss of positional identity of the hydrogen and carbon atoms in [t‐C3H8N]+ metastable cations prior to fragmentation in the gas phase with loss of ethylene, has been demonstrated by 2H and 13C labelling experiments. The scrambling reaction is interpreted as a rearrangement in competition with the high activation energy unimolecular decompositions. The study of this fragmentation process indicates the occurrence of a primary isotope effect discriminating in favour of 2H and 13C retention in the original methylene group.