Dimethyldioxirane

Dimethyldioxirane (DMDO) is the organic compound with the formula (CH3)2CO2.^[1] It is the dioxirane derived from acetone and can be viewed as the monomer of acetone peroxide. It is a powerful selective oxidizing agent that finds some use in organic synthesis. It is known only in the form of a dilute solution, usually in acetone, and hence the properties of the pure material are largely unknown.^[2]

DMDO is not commercially available because of chemical instability. DMDO can be prepared as dilute solutions (~0.1 M) by treatment of acetone with potassium peroxymonosulfate KHSO

5, usually in the form of Oxone (2KHSO₅·KHSO₄·K₂SO₄).^[3]



The preparation of DMDO is rather inefficient (typical yields < 3%) and typically only yields a relatively dilute solution in acetone (only up to approximately 0.1 M). This is tolerable as preparation uses inexpensive substances: acetone, sodium bicarbonate, and oxone. Cold solutions (−10 to −20 °C) of DMDO are stable for days. Decomposition is accelerated by light and by heavy metals. The concentration of DMDO may be assayed immediately prior to its use.^[2]

Methyl(trifluoromethyl)dioxirane (H3C)(F3C)CO2 can be similarly prepared from methyl trifluoromethyl ketone. It is a stronger oxidant than DMDO.

DMDO is most commonly used for the oxidation of alkenes to epoxides.^[4] One advantage of using DMDO is that the only byproduct of oxidation is acetone, a fairly innocuous and volatile compound. DMDO oxidations are particularly mild, sometimes allowing oxidations which might not otherwise be possible.

Despite its high reactivity, DMDO displays good selectivity for electron-rich olefins. DMDO will also oxidize several other functional groups. For example, DMDO will oxidize primary amines to nitro compounds and sulfides to sulfoxides. In some cases, DMDO will even oxidize unactivated C-H bonds:



DMDO can also be used to convert nitro compounds to carbonyl compounds (Nef reaction).^[5]