Charge stripping mass spectra: A method for identifying isomeric [C5H8]+˙ and [C3H6]+˙ ions

Charge stripping (collisional ionization) mass spectra are reported for isomeric [C5H8]+˙ and [C3H6]+˙ ions. The results provide the first method for adequately quantitatively determining the structures and abundances of these species when they are generated as daughter ions. Thus, loss of H2O from the molecular ions of cyclopentanol and pentanal is shown to produce mixtures of ionized penta‐1,3‐ and ‐1,4‐dienes. Pent‐1‐en‐3‐ol generates [penta‐1,3‐diene]+˙. [C3H6]+˙ ions from ionized butane, methylpropane and 2‐methylpropan‐1‐ol are shown to have the [propene]+˙ structure, whereas [cyclopropane]+˙ is produced from ionized tetrahydrofuran, penta‐1,3‐diene and pent‐1‐yne.