Synthesis of 1,2,4-trioxanes and 1,2,4-trioxepanes by N-halogenosuccinimide-mediated cyclisations of unsaturated hydroperoxyacetals

Abstract

Ozonolyses of vinyl ethers 1a–c in CH₂Cl₂ in the presence of allylic and homoallylic alcohols 3a–c give in each case the corresponding unsaturated hydroperoxy acetals 4a–h, derived from capture of the carbonyl oxides 2a–c by the unsaturated alcohols. N-Halogenosuccinimide-mediated cyclisations of the hydroperoxides give the corresponding 1,2,4-trioxanes and/or 1,2,4-trioxepanes, depending on the structure of the hydroperoxides and the identity of the N-halogenosuccinimides.