Dimethyldioxirane (DMDO), also referred to as Murray's reagent in reference to Robert W. Murray, is a

dioxirane In chemistry, dioxirane is a compound with formula , whose molecule consists of a ring with one carbon and two oxygen atoms, and two hydrogen atoms attached to the carbon. It is a heterocyclic compound, the smallest cyclic organic peroxide. Th ...

derived from

acetone Acetone (2-propanone or dimethyl ketone), is an organic compound with the formula . It is the simplest and smallest ketone (). It is a colorless, highly volatile and flammable liquid with a characteristic pungent odour. Acetone is miscib ...

and can be considered as a monomer of acetone peroxide. It is a powerful yet selective oxidizing agent which finds use in

organic synthesis Organic synthesis is a special branch of chemical synthesis and is concerned with the intentional construction of organic compounds. Organic molecules are often more complex than inorganic compounds, and their synthesis has developed into one o ...

. 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.

Synthesis

DMDO is not commercially available because of its instability. DMDO can be prepared as dilute solutions (~0.1 M) by treatment of

with

potassium peroxymonosulfate Potassium peroxymonosulfate is widely used as an oxidizing agent. It is the potassium salt of peroxymonosulfuric acid. Usually potassium peroxymonosulfate refers to the triple salt known as oxone. The standard electrode potential for potassium ...

, usually in the form of

Oxone Potassium peroxymonosulfate is widely used as an oxidizing agent. It is the potassium salt of peroxymonosulfuric acid. Usually potassium peroxymonosulfate refers to the triple salt known as oxone. The standard electrode potential for potassium ...

(2KHSO₅·KHSO₄·K₂SO₄). : Dimethyldioxirane Synthesis V

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:

sodium bicarbonate Sodium bicarbonate (IUPAC name: sodium hydrogencarbonate), commonly known as baking soda or bicarbonate of soda, is a chemical compound with the formula NaHCO3. It is a salt composed of a sodium cation ( Na+) and a bicarbonate anion ( HCO3−) ...

, and

(commercially known as "oxone"). The solution can be stored at low temperatures and its concentration may be assayed immediately prior to its use. The more active compound methyl(trifluoromethyl)dioxirane can be similarly prepared from methyl trifluoromethyl ketone.

Stability

Solutions are stable under refrigeration (−10 to −20 °C) for up to a week. The rate of decomposition will increase upon exposure to light or heavy metals.

Uses

The most common use for DMDO is the oxidation of alkenes to epoxides. One particular 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. In fact, DMDO is considered the reagent of choice for epoxidation, and in nearly all circumstances is as good as or better than peroxyacids such as ''meta''-chloroperoxybenzoic acid (mCPBA). Despite its high reactivity, DMDO displays good selectivity for olefins. Typically, electron deficient olefins are oxidized more slowly than electron rich ones. DMDO will also oxidize several other functional groups. For example, DMDO will oxidize primary

amine In chemistry, amines (, ) are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia (), wherein one or more hydrogen atoms have been replaced by a substituen ...

s to

nitro compound In organic chemistry, nitro compounds are organic compounds that contain one or more nitro functional groups (). The nitro group is one of the most common explosophores (functional group that makes a compound explosive) used globally. The nitr ...

s and

sulfide Sulfide (British English also sulphide) is an inorganic anion of sulfur with the chemical formula S2− or a compound containing one or more S2− ions. Solutions of sulfide salts are corrosive. ''Sulfide'' also refers to chemical compounds lar ...

s to

sulfoxide In organic chemistry, a sulfoxide, also called a sulphoxide, is an organosulfur compound containing a sulfinyl () functional group attached to two carbon atoms. It is a polar functional group. Sulfoxides are oxidized derivatives of sulfides. E ...

s. In some cases, DMDO will even oxidize unactivated C-H bonds: : DMDO can also be used to convert

s to carbonyl compounds (

Nef reaction In organic chemistry, the Nef reaction is an organic reaction describing the acid hydrolysis of a salt of a primary or secondary nitroalkane () to an aldehyde () or a ketone () and nitrous oxide (). The reaction has been the subject of sever ...

).{{cite journal, first1=Waldemar, last1=Adam, first2=Mieczyslaw, last2=Makosza, first3=Chantu R., last3=Saha-Möller, first4=Cong-Gui, last4=Zhao, title=A Mild and Efficient Nef Reaction for the Conversion of Nitro to Carbonyl Group by Dimethyldioxirane (DMD) Oxidation of Nitronate Anions, journal=

Synlett ''Synlett'' is an international scientific journal for accounts and rapid communications of original contributions of fundamental research in synthetic organic chemistry. The impact factor of this journal is 2.419 (2017). ''Nature'' featured a br ...

, year=1998, volume=1998, issue=12, pages=1335–1336, doi=10.1055/s-1998-1947 :

References

Reagents for organic chemistry Organic peroxides Dioxiranes Oxidizing agents

Synthesis

Stability

Uses

See also

References