Dimethyldioxirane

Dimethyl dioxirane (DMDO) is a highly reactive electrophilic oxidant belonging to the family of dioxiranes, a class of highly strained three‑membered rings containing two adjacent oxygen atoms and one carbon atom. In DMDO, the ring carbon bears two methyl substituents, giving a compact, potent oxygen-transfer reagent. It is typically generated in situ in acetone solution and used directly for oxidations.

Preparation and handling: DMDO is prepared by oxidizing acetone with an oxygen‑bearing oxidant, commonly potassium peroxymonosulfate (Oxone) in acetone at low temperature (around 0 to 5 °C). The process yields a solution containing DMDO that can be employed immediately for oxidation. DMDO is unstable at room temperature and decomposes rapidly; it is therefore prepared fresh and kept cold, often in a sealed, inert environment. It can be delivered as a solution in acetone or, in some setups, as a gas.

Reactivity and applications: DMDO transfers an oxygen atom to alkenes to form epoxides under mild conditions, frequently with good rate and stereochemical outcomes. It also oxidizes sulfides to sulfoxides or sulfones, depending on the oxidant loading and conditions. Compared with traditional peracids, DMDO can offer complementary selectivity and can be advantageous for sensitive substrates. Its high reactivity makes it powerful but also challenging to handle, limiting its practical use to specialized settings.

Safety and scope: As an energetic, highly oxidizing species, DMDO requires careful handling, cold storage, and immediate use after generation. It is not typically used for large‑scale syntheses due to instability and cost considerations, but remains a useful tool in academic and specialized synthetic contexts.