On the Triggering of Free Radical Reactivity of Dimethyldioxirane

Performing the reaction in the presence of CCl3Br, and/or in inert gas atmosphere, dramatically changes the reaction kinetics, rate-law and product distribution of adamantane oxyfunctionalization by dimethyldioxirane (1a). The kinetics of decomposition of the dioxirane is also markedly influenced by the addition of CCl3Br and by depletion of O2 gas. The data suggest that these conditions can trigger dioxirane radical reactions; these are widely different from the straightforward, highly selective concerted O-insertion into C-H bonds which would take place in the absence of CCl3Br and of conditions inducing radical reactivity