Decomposition of dioxetane induced by electron transfer from a photoexcited lanthanide ion

The photodecomposition of adamantylideneadamantane-1,2-dioxetane (1) in the presence of Ce³⁺ is discovered. Electron transfer plays a dominant role in the reaction mechanism. The photoirradiation of solutions of1 and CeCl₃ within the absorption region of the latter leads to the decomposition of1 with the initial quantum yield φ=0.29±0.03. The reaction is caused by the dynamic extinction of the photoluminescence of^*Ce³⁺ ions by dioxetane1. Adamantanone is the main product of the photocatalytic reaction. However, side products of the interaction of the intermediate 1,4-dioxyradical anion with the solvent are also formed. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1824–1826, October, 1993.