2-Methylimidazole Property

Melting point:

142-143 °C (lit.)

Boiling point:

267-268 °C (lit.)

Density 

1.0500 (rough estimate)

vapor pressure 

<1 mm Hg ( 0 °C)

refractive index 

1.4970 (estimate)

Flash point:

155 °C

storage temp. 

2-8°C

solubility 

780g/l

pka

14.44±0.10(Predicted)

form 

Crystalline Powder

color 

White to light yellow

PH Range

10.5

PH

10.5-11.5 (100g/l, H2O, 20℃)

Water Solubility 

Soluble in water and ethanol.

BRN 

1368

InChIKey

LXBGSDVWAMZHDD-UHFFFAOYSA-N

LogP

0.22 at 25℃

CAS DataBase Reference

693-98-1(CAS DataBase Reference)

NIST Chemistry Reference

1H-Imidazole, 2-methyl-(693-98-1)

IARC

2B (Vol. 101) 2013

EPA Substance Registry System

2-Methylimidazole (693-98-1)

Safety

Hazard Codes 

C

Risk Statements 

22-34

Safety Statements 

26-36/37/39-45-25

RIDADR 

UN 3259 8/PG 2

WGK Germany 

2

RTECS 

NI7175000

Autoignition Temperature

>600 °C DIN 51794

Hazard Note 

Harmful/Corrosive

TSCA 

Yes

HazardClass 

8

PackingGroup 

III

HS Code 

29332990

Hazardous Substances Data

693-98-1(Hazardous Substances Data)

Toxicity

LD50 orally in Rabbit: 1500 mg/kg

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Danger

Hazard statements

H302Harmful if swallowed

H314Causes severe skin burns and eye damage

H351Suspected of causing cancer

Precautionary statements

P260Do not breathe dust/fume/gas/mist/vapours/spray.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P301+P312IF SWALLOWED: call a POISON CENTER or doctor/physician IF you feel unwell.

P303+P361+P353IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

2-Methylimidazole Chemical Properties,Usage,Production

Detection method

Fluorescence detection method: Using o-phenylenediamine as the carbon source and phytic acid as the phosphorus source, two P-rich carbon quantum dots RCD and BCD were successfully synthesized by changing the reaction temperature and time of the hydrothermal method. The study found that the red-emitting RCD can achieve sensitive detection of 2-Methylimidazole, while 2-methylimidazole has no obvious quenching effect on the blue-emitting BCD, which makes RCD a sensitive, fast and selective fluorescence sensor for 2-methylimidazole detection. Under the optimal experimental conditions, the fluorescence intensity of RCDs decreases with the increase of 2-methylimidazole concentration; the carbon quantum dot sensor shows a good linear relationship in the detection of 2-methylimidazole concentration in the range of 5 ~ 110 µM, and the minimum detection limit is 0.61 µM (S/N = 3). The sensor can detect 2-methylimidazole in lake water and can be used for the detection of actual samples^[2].

Chemical Properties

2-Methylimidazole is a white to light yellow crystalline powder with an amine-like odor. It is highly soluble in polar organic solvents. Insoluble in ether and cold benzene, easily soluble in water, alcohols and ketones. Irritating to skin and mucous membranes. Mice orally LD50 1400mg/kg.

Chemical Properties

The 2-methylimidazole molecule is approximately planar, and the maximum deviation of all non-H atoms from the plane of the least squares imidazole is 0.006(2)?. N–H··· N hydrogen bonds link molecules together to form infinite chains of hydrogen bond pattern C(4). The crystal of 2-methylimidazole is in orthorhombic crystal system with space group P2₁2₁2₁ (Z = 4), lattice parameters: a = 5.9957(12) ?, b = 8.1574(16) ? and c = 9.7010(19) ?, V = 474.47(16) ?[1].

Uses

2-Methylimidazole is a monomethylated imidazole that can be used as a building block in the preparation of a wide range of biologically active compounds. 2-Methylimidazole as well as other imidazoles can be use as catalyst for refolding of enhanced coloured fluorescent protein. 2-Methylimidazole has been identified as a byproduct of fermentation and is detected in foods and mainstream and side-str eam tobacco smoke.

Uses

2-Methylimidazole is used as a raw material for the preparation of nitroimidazole antibiotics, which is useful in combat anaerobic bacterial and parasitic infections. It acts as a ligand in coordination chemistry. It is also employed as a hardener or accelerator for epoxy resin and auxiliary agent for textile dyes. Further, it acts as a catalyst for refolding of enhanced colored fluorescent protein. It is also useful as a building block in the synthesis of biologically active compounds. In addition to this, it is used as an active pharmaceutical ingredient intermediate such as metronidazole and dimetridazole.

Preparation

2-Methylimidazole is prepared by condensation of glyoxal, ammonia and acetaldehyde, a Radziszewski reaction. It is widely used as a polymeriza tion cross-linking accelerator and a hardener for epoxy resin systems for semiconductor potting compounds and soldering masks.
It is obtained by eliminating dehydrogenation of 2-methylimidazoline. 2-methylimidazoline heated to melt (melting point 107 ℃), carefully add active nickel, raise the temperature to 200-210 ℃ reaction 2h. cool down to below 150 ℃, add water to dissolve, while hot pressure filtration, separation of active nickel, the filter Chemicalbook liquid concentrated to a temperature of 140 ℃ or more, put the material cooling that 2-methylimidazole. Use the method to produce purity of ≥ 98% of the product, 1t product consumption of ethylenediamine (95%) 1095kg, acetonitrile 975kg. better method is to use glyoxal and aldehyde as raw materials.

General Description

It is a white or colorless solid that is highly soluble in polar organic solvents and water. It is a precursor to a range of drugs and is a ligand in coordination chemistry.

Hazard

Possible carcinogen.

Flammability and Explosibility

Not classified

Purification Methods

Recrystallise 2-methylimidazole from *benzene or pet ether. The picrate has m 215o (from H2O). [Beilstein 23 III/IV 594, 23/5 V 35.]

Toxicity evaluation

2-Methylimidazole is harmful if swallowed and may cause severe skin burns and eye damage from exposure. It is also associated with adverse effects such as neurotoxins, reproductive toxins and toxic pneumonia. In vitro studies have shown a mouse LD50: 480 mg/kg (intraperitoneal); 1400 mg/kg (oral).

References

[1] Hachu?a B, et al. Crystal and Molecular Structure Analysis of 2-Methylimidazole. Journal of Chemical Crystallography, 2009; 40: 201–206.
[2] ZHENGYUAN DAI. Synthesis of P-Rich Carbon Quantum Dots for Sensitive Fluorescent Detection of 2-Methylimidazole.[J]. Journal of Fluorescence, 2024. DOI:10.1007/s10895-024-03946-9.