Thiophene, dioxirane oxidation

Thiophene, dioxirane oxidation, 1156 Thiourea, dialkyl peroxide synthesis, 706 1,4-Thioxane, oxidation, 805-6 Thiyl radicals, triplet oxygen domino reactions, 221-3, 224, 225, 226 THPO (1,2,3,4-tetrahydronaphthyl hydroperoxide), 331-2 Thromboxanes, from arachidonic hydroperoxides, 612... 

The by far more common and preparatively valuable dioxirane oxidation of divalent sulfur substrates is that of sulfides, to produce either sulfoxides or sulfones . Since sulfoxides are considerably less reactive than sulfides, the reaction outcome may be conveniently controlled by the stoichiometry of the oxidant For example, in the low-temperature oxidation of thiophene by an excess of DMD, the corresponding 1,1-dioxide (sulfone) has been obtained, albeit in low yield (equation 20). This is the first preparatively useful method for isolating this elusive sulfone, which also accentuates the importance of the neutral and anhydrous conditions under which the oxidations with the isolated DMD may be conducted. 

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