Dimethylglyoxime is a
chemical compound described by the formula CH
3C(NOH)C(NOH)CH
3. Its abbreviation is dmgH
2 for neutral form, and dmgH
− for anionic form, where H stands for hydrogen. This colourless solid is the di
oxime derivative of the di
ketone
In organic chemistry, a ketone is a functional group with the structure R–C(=O)–R', where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group –C(=O)– (which contains a carbon-oxygen double bo ...
butane-2,3-dione (also known as
diacetyl). DmgH
2 is used in the analysis of
palladium or
nickel. Its
coordination complexes are of theoretical interest as models for enzymes and as catalysts. Many related
ligands
In coordination chemistry, a ligand is an ion or molecule (functional group) that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's electro ...
can be prepared from other diketones, e.g.
benzil.
Preparation
Dimethylglyoxime can be prepared from
butanone first by reaction with
ethyl nitrite to give
biacetyl monoxime
Diacetyl monoxime is a chemical compound described by the formula CH3C(O)C(NOH)CH3. This colourless solid is the monooxime derivative of the diketone butane-2,3-dione (also known as diacetyl and biacetyl). Its biological effects include inhibitin ...
. The second
oxime is installed using sodium
hydroxylamine monosulfonate:
Complexes
Dimethylglyoxime forms complexes with metals including
nickel,
palladium and
cobalt.
These complexes are used to separate those cations from solutions of metal salts and in
gravimetric analysis. It is also used in
precious metals refining to precipitate
palladium from solutions of
palladium chloride.
References
{{Authority control
Ketoximes
Chelating agents