Mechanistic Significance of <i>Perepoxide Trapping</i> Experiments, with Epoxide Detection, in <sup>1</sup>Δ<sub>g</sub> Dioxygen Reactions with Alkenes

The reactions of <sup>1</sup>O<sub>2</sub> with alkenes can share open-chain diradicals or cyclic peroxiranes as common polar intermediates. The latter in particular has been postulated on the basis of trapping experiments, which exploit the capability of reducing agents (R) to extract an oxygen atom from the putative perepoxide, to generate an epoxide. This theoretical study illustrates that trapping experiments cannot distinguish between a peroxirane and an open-chain intermediate pathway, because an epoxide is the shared outcome of the attack by R.