Competitive Hydrogen‐Atom Abstraction versus Oxygen‐Atom and Electron Transfers in Gas‐Phase Reactions of [X₄O₁₀]^.+ (X=P, V) with C₂H₄

Why so different? The comparison of the reaction of "bare" [P4O10](·+) and [V4O10](·+) with ethene by mass-spectrometric and computational studies permits insight into mechanistic aspects of the competition between C-H bond activation and oxygen-atom and electron transfers. Whereas [P4O10](·+) reacts by homolytic C-H bond cleavage and electron transfer, the isostructural [V4O10](·+) shows only oxygen-atom transfer (see picture).