1,3-Dimethyl-2-imidazolidinone (DMI) is a cyclic
urea
Urea, also called carbamide (because it is a diamide of carbonic acid), is an organic compound with chemical formula . This amide has two Amine, amino groups (–) joined by a carbonyl functional group (–C(=O)–). It is thus the simplest am ...
used as a high-boiling
polar aprotic solvent
A solvent (from the Latin language, Latin ''wikt:solvo#Latin, solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a Solution (chemistry), solution. A solvent is usually a liquid but can also be a solid, a gas ...
. This colourless, highly polar solvent has high thermal and chemical stability. Together with
homologous solvent
DMPU
''N'',''N''′-Dimethylpropyleneurea (DMPU) is a cyclic urea sometimes used as a polar, aprotic organic solvent. Along with the dimethylethyleneurea, it was introduced as an analog of tetramethylurea.
In 1985, Dieter Seebach showed that it is ...
, since the 1970s it serves as an analog of
tetramethylurea
Tetramethylurea is the organic compound with the formula (Me2N)2CO. It is a substituted ureas, urea. This colorless liquid is used as an Protic solvent, aprotic-polar solvent, especially for aromatic compounds and is used e. g. for Grignard reag ...
.
It can be prepared from
1,2-dimethylethylenediamine
N,N'-Dimethylethylenediamine (DMEDA) is the organic compound with the formula (CHNH)CH. It is a colorless liquid with a fishy odor. It features two secondary amine functional groups. Regarding its name, N and N' indicate that the methyl groups ...
by reaction with
phosgene
Phosgene is an organic chemical compound with the formula . It is a toxic, colorless gas; in low concentrations, its musty odor resembles that of freshly cut hay or grass. It can be thought of chemically as the double acyl chloride analog of ...
.
History
In 1940
Du Pont applied for a patent on
acetylene
Acetylene (Chemical nomenclature, systematic name: ethyne) is a chemical compound with the formula and structure . It is a hydrocarbon and the simplest alkyne. This colorless gas is widely used as a fuel and a chemical building block. It is u ...
storage in many polar organic solvents, one of which was 1,3-dimethyl-2-imid azolidone. The company filed another patent on a method of synthesizing the same compound, albeit called s-dimethylethyleneurea, in 1944.
Soon thereafter
William Boon
William Robert Boon Fellow of the Royal Society, FRS Fellow of the Royal Society of Chemistry, FRSC (20 March 1911 – 28 October 1994) was a British chemist, known for developing the herbicide paraquat.
Early life
He was educated at St Dunstan ...
from the
Imperial Chemical Industries
Imperial Chemical Industries (ICI) was a British Chemical industry, chemical company. It was, for much of its history, the largest manufacturer in Britain. Its headquarters were at Millbank in London. ICI was listed on the London Stock Exchange ...
published a different synthesis method of what he called 1:3-dimethyliminazolid-2-one. The compound was more closely studied in the 1960s, with its adoption as a solvent starting in the 1970s.
Solvent
DMI has excellent solvating ability for both inorganic and organic compounds. In many applications, DMI (as well as DMPU) can be used as a substitute or replacement for the carcinogenic solvent
HMPA
Hexamethylphosphoramide, often abbreviated HMPA, is a phosphoramide (an amide of phosphoric acid) with the formula This colorless liquid is used as a solvent in organic synthesis.
Structure and reactivity
HMPA is the oxide of tris(dimethylamino ...
. Compared to the 6-atom ring analog, it has an advantage of lower viscosity (1.9 vs. 2.9 cP at 25°C).
DMI is used in a variety of applications including detergents, dyestuffs, electronic materials and in the manufacture of polymers.
DMI is toxic in contact with skin.
DMI
at TCI
References
{{DEFAULTSORT:Dimethyl-2-Imidazolidinone, 1,3-
Solvents
Amide solvents
Imidazolidinones
Methyl compounds