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. ...
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 miscible wi ...
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
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 miscible wi ...
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 p ...
, 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 p ...
(2KHSO
5·KHSO
4·K
2SO
4).
:

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
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 miscible wi ...
,
sodium bicarbonate, and
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 p ...
(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
In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula . In formulas, the group is often abbreviated as Me. This hydrocarbon group occurs ...
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 substituent su ...
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 nit ...
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 l ...
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
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 nit ...
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 several ...
).
[{{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
:
See also
*
Shi epoxidation
The Shi epoxidation is a chemical reaction described as the asymmetric epoxidation of alkenes with oxone (potassium peroxymonosulfate) and a fructose-derived catalyst (1). This reaction is thought to proceed via a dioxirane intermediate, generated ...
References
Reagents for organic chemistry
Organic peroxides
Dioxiranes
Oxidizing agents