The singlet oxygenation of alkenes 1 gives the corresponding dioxetanes 2, whose thermal stability and half-life of Chemiluminescence induced by TBAF (NBun4F) are significantly affected by the 3-alkoxyl group.
EtO < i-PrO ⪢ tert-BuO. On treatment with tetrabutylammonium fluoride in DMSO, dioxetanes (10e - 10h) bearing a m-siloxyphenyl decompose rapidly to emit intense blue light with ΦCL > 0.2. For the base-induced decomposition of 10e - 10h, the order of rate of decomposition is MeO < EtO < i-PrO < tert-BuO.