1,3-Dimethyl-2-imidazolidinone

1,3-Dimethyl-2-imidazolidinone DMI environmental solvent

General name：1,3-Dimethyl-2-imidazolidinone；N,N'-Dimethylethyleneurea; 1,3-Dimethylimidazolidin-2-one; DMEU;DMI

Molecular formula：C5H10N2O

Structural formula：

Molecular weight：114.15
CAS NO: 80-73-9

EC Number201-304-8

Properties：colorless transparent liquid,melting point:220℃（100.52kPa）.

Density:1.044.
Quality standard：≥99% .
　　

Group:Intermediates

Description1,3-Dimethyl-2-imidazolidinon is a cyclic urea used as a high-boiling polar aprotic solvent. and its chemical formula C5H10N2O.

Synonyms:1,3-DMI,karbomostsem,1,3-dimethylimidazolin-2-one,1,3-Dimethyl-2-imida,1,3-dimethylimidazolidi,1,3-Dimethylimidazolidin-2-one,1,3-Dimethyl-2-imidazolidi,rhonite1,dimethyl-2-imidazolidi,1,3-DIMETHYL-2-IMIDAZOLIDI ,DMEU,pharmaceutical intermediate,Karbomos,N,N'-dimethylimidazolidi,N,N'-dimethyl-2-imidazolidi,1,3-Dimethyl-2-imidazolidinone,N,N'-Dimethylethyleneurea,1,3-Dimethylethyleneurea,N,N'-Dimethylimidazolidinone,1,3-Dimethylimidazolidin-2-on,1,3-Dimethylethyl-2-imidazolidinon,Dimethylethylenharnstoff,Dimethylethylharnstoff

Application：mainly used as solvents.

High boiling point, high flash point, low melting point, very low toxicity, negligible harm to the human body, but also reduce pollution to the environment because it has a strong solubility, can dissolve organic matter, inorganic matter, resin, polymer, etc., but also with other high boiling point solvents miscibility;Excellent stability under hot strong alkali and acid conditions, water resistance and light, oxygen stability widely used in refining, dyes/pigments, microelectronics, engineering plastics, pesticides, cleaning and surface treatment。

1. Reaction solvent:

DMI is a particularly effective reaction solvent due to its excellent thermal and chemical stability, its ability to dissolve inorganic, organic compounds and a variety of resins, and its catalytic role as an aprotic polar solvent.Using DMI can improve the yield and effectively control the side effects while reducing the reaction time.

DMI can effectively promote various nucleophilic substitution reactions, such as the synthesis of phenyl ether derivatives, amino compounds and fluorobenzene derivatives.Its high dielectric constant and solvation to cations can catalyze anionic nucleophilic reactions.These synthetic products are used as intermediates in the synthesis of agricultural chemicals, dyes and monomers of high performance resins. 

2. Petroleum products:

DMI tools with high boiling point and high heat stability and not easy to form azeotrope with other substances, so it can be a liquid countercurrent washing, extraction distillation and extraction, reflux distribution used in many industrial processes such as: because DMI can dissolve and unsaturated hydrocarbons, aromatic compounds are insoluble alkanes, so it is very good BTX (benzene, toluene and xylene) extraction agent.

3.Polymer reaction solvent:

DMI is the only solvent suitable for the production of heat-resistant thermoplastics. It can also be used effectively as a solvent for various polymer synthesis processes and as a mold cleaning agent for polymerization reactions and plastic molding.In the production of polyamide and polyimide resins, DMI can accelerate the formation of amide and imide groups and obtain polymers with high molecular weight. The solution obtained is suitable for solution spinning and can be used to obtain high-temperature polyimide fibers.In the production of polyphenylene sulfide resin (PPS), electronic materials with minimal organic impurities can be obtained by using DMI.In the production of polyphenyl ether sulfone resin, DMI can effectively control the occurrence of side reactions and obtain high quality polymer products.When polyimide and polysulfone resin films are processed and polyether ketone resin films are extended, DMI treatment makes the films more uniform. 

4. Photoetching process exfoliator:

DMI can be used as electrolyte solvent for high performance lithium batteries due to its low viscosity and high dielectric constant.In addition, its strong permeability, high boiling point and high temperature resistance characteristics, it can also be used as a silicon chip photoresist stripping agent.It can greatly simplify the stripping process and accelerate the production rate of the chip.

5. Detergent:

DMI is added to a mixture of surfactant, alkali, alcohol and polyoxyethylene alkyl ether to produce a powerful detergent.Since DMI dissolves dirt easily, it can also be used to make an efficient cleaning solution for glass and metal cleaning.

6 .Dyes and pigments:

DMI is used as a solvent component to mix with dyes and pigments to produce ink that can be sprayed with cloth with sharp contrast and clear image.

7. Surface treatment agent:

DMI can be used as a surface treatment agent to improve the bonding strength of ABS, polyimide, PPS, ptFE and other materials with epoxy adhesives.

8. In the field of liquid crystal materials:

high quality porous ultrafiltration membrane can be obtained, which is a liquid crystal locator with stable storage performance;

Nucleophilic substitution, reduction, oxidation, elimination, halogen exchange reaction under alkaline conditions, Kolbe-Schmitt

The applications of reaction and Ullmann reaction have good effects.

9.DMI and NMP(N-methylpyrrolidone)

DMI is similar to NMP in structure, performance and application domain, but there are significant differences between them in some performance:

 A Toxicity:

Although NMP is a low volatile, low toxic solvent, but the latest research found that NMP has potential reproductive toxicity, some parts of the United States and Europe have restricted its use, such as paint, graffiti cleaning agents, pesticides and other human body may be exposed to a large number of NMP steam use banned.Tighter restrictions are likely in the future.There has been no reported toxicity of DMI, which has been able to widely replace the strong carcinogenic solvent HMPA(Hexamethylamide).

B. Resistance to hydrolysis:

Both NMP and DMI are lactamides.Because the amide bond is easy to hydrolyze, the use conditions of amide solvents are limited. For example, DMF spontaneously decomposes into dimethylamine and carbon monoxide at high temperature (350℃), and also slightly decomposes at room temperature.In the presence of strong alkali (such as KOH, NaOH, AcONa), it will decompose rapidly at room temperature without water, and may explode at high temperature.NMP is more stable than DMF, but it is also prone to decomposition under alkaline conditions (about 50-70% decomposition of 4% sodium hydroxide in 8h), and stable under acidic conditions.On the one hand, the conjugation effect of DMI reduces the dipole and carbonyl reactivity due to the structure of urea.On the other hand, the five atoms coplanar in the ring make it less likely that the nucleophile will attack the carbonyl group in the ring.So DMI is quite stable at high temperature and alkalinity, and does not decompose rapidly.Compared with NMP, THE application scope of DMI is extended and can be applied to the reaction under alkaline conditions.

C. Organic reactions

The pKa of N atom on DMI corresponds to acid is larger than that of NMP, which means that DMI is more suitable for nucleophilic substitution reaction solvent.At the same time, DMI has a higher boiling point and stability, suitable for the need to prevent solvent volatilization.At the same time, DMI is more soluble, no matter inorganic, organic matter, polymer can form solution, so that the reaction system is uniform, promote the reaction fully and quickly.In particular, DMI can accelerate the reaction rate and yield of metal salts (LiCl, CuI, etc.) as catalyst.