On the loss of ethylene from [C3H7O]+ ions of structure

The results of some 3C and 2H labelling experiments plus some measurements of reaction thermochemistry and translational energy releases, permit a significant simplification of the mechanistic pathways by which [C3H7O]+ ions of structure fragment by loss of C2H4. The relationships between these ions and some of their isomeric forms are explored and clarified.