1-Methylimidazole Property

Melting point:

−60 °C(lit.)

Boiling point:

198 °C(lit.)

Density 

1.03 g/mL at 25 °C(lit.)

vapor pressure 

0.4 mm Hg ( 20 °C)

refractive index 

n20/D 1.495(lit.)

Flash point:

198 °F

storage temp. 

Store below +30°C.

solubility 

Chloroform (Slightly), Methanol (Slightly)

form 

Liquid

pka

6.95(at 25℃)

Specific Gravity

1.031

color 

Clear colorless to yellow

PH

9.5-10.5 (50g/l, H2O, 20℃)

PH Range

9.5 - 11.5 at 100 g/l at 20 °C

explosive limit

2.7-15.7%(V)

Water Solubility 

Miscible with water.

Sensitive 

Hygroscopic

BRN 

105197

Stability:

Stable, but moisture sensitive. Incompatible with acids, acid anhydrides, strong oxidizing agents, moisture, carbon dioxide, acid chlorides.

InChIKey

MCTWTZJPVLRJOU-UHFFFAOYSA-N

LogP

-0.19 at 25℃

CAS DataBase Reference

616-47-7(CAS DataBase Reference)

NIST Chemistry Reference

1H-Imidazole, 1-methyl-(616-47-7)

EPA Substance Registry System

1H-Imidazole, 1-methyl- (616-47-7)

Safety

Hazard Codes 

C,Xn,F,T

Risk Statements 

21/22-34-19-11-20/21/22-52/53-24-22-40-37-21

Safety Statements 

26-36-45-1/2-36/37/39-16-33-29-61

RIDADR 

UN 3267 8/PG 2

WGK Germany 

1

RTECS 

NI7000000

F 

3-10

Autoignition Temperature

977 °F

TSCA 

Yes

HazardClass 

8

PackingGroup 

III

HS Code 

29332990

Toxicity

LD50 orally in Rabbit: 1144 mg/kg LD50 dermal Rabbit > 400 - < 640 mg/kg

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Danger

Hazard statements

H302Harmful if swallowed

H311Toxic in contact with skin

H314Causes severe skin burns and eye damage

Precautionary statements

P270Do not eat, drink or smoke when using this product.

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

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

P301+P330+P331IF SWALLOWED: Rinse mouth. Do NOT induce vomiting.

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.

1-Methylimidazole Chemical Properties,Usage,Production

Chemical Properties

1-Methylimidazole or N-methylimidazole is an aromatic heterocyclic organic compound with the formula CH3C3H3N2. It is a colorless to yellow liquid, with an amine-like odor. It is miscible with water. N-methylimidazole is an important raw material for the synthesis of pharmaceutical intermediates, used in the preparation of losartan, nizofenone, 1-Methyl-1H-imidazole-5-carbonyl chloride hydrochloride and naphazoline hydrochloride, etc. It is also used as a specialty solvent, a base, and as a precursor to some ionic liquids.

Uses

1-Methylimidazole is an aprotic solvent. It is a derivative of imidazole used in the production of pharmaceuticals, pesticides, ion exchange resins, dye intermediates, textile auxiliaries, photographic chemicals, and corrosion inhibitors. It can also be used as a catalyst for the manufacture of polyurethane and a curing agent for epoxy resins. For example, when 1-methylimidazole is added to an aqueous diethylenetriamine (DETA) solution, high CO2 loading can be achieved through phase separation of the absorbent during CO2 absorption[1].

Definition

ChEBI: 1-methyl-1H-imidazole is a 1H-imidazole having a methyl substituent at the N-1 position. It is a metabolite of 1-methyl-2-thioimidazole (methimazole). It inhibits bone resorption.

Preparation

1-Methylimidazole is prepared mainly by two routes industrially. The main one is acid-catalysed methylation of imidazole by methanol. The second method involves the Radziszewski reaction from glyoxal, formaldehyde, and a mixture of ammonia and methylamine.
(CHO)2 + CH2O + CH3NH2 + NH3 → H2C2N(NCH3)CH + 3 H2O
The compound can be synthesized on a laboratory scale by methylation of imidazole at the pyridine-like nitrogen and subsequent deprotonation. Similarly, 1-methylimidazole may be synthesized by first deprotonating imidazole to form a sodium salt followed by methylation.
H2C2N(NH)CH + CH3I → [H2C2(NH)(NCH3)CH]I
[H2C2(NH)(NCH3)CH]I + NaOH → H2C2N(NCH3)CH + H2O + NaI

General Description

This product has been enhanced for catalysis. 1-Methylimidazole is a derivative of imidazole that is utilized in the manufacture of such classes of items as pharmaceuticals, pesticides, ion-exchange resins, dye intermediates, textile auxiliaries, photographic chemicals, and corrosion inhibitors. It is also used as a catalyst for manufacturing polyurethanes and a curing agent for epoxy resins.

Flammability and Explosibility

Not classified

Purification Methods

Dry it with sodium metal and then distil it. Store it at 0o under dry argon. The picrate has m 159.5-160.5o (from H2O). [Beilstein 23 III/IV 568.]

Toxicity evaluation

Acute toxicity:Harmful if swallowed. Toxic in contact with skin. LD50 Oral:1144 mg/kg, LD50 Dermal:400-640 mg/kg.

References

[1] You J, et al. Effect of 1-Methylimidazole on CO2 Absorption by Diethylenetriamine (DETA) Aqueous Solutions. Chemical Engineering & Technology, 2017; 40: 2238-2242.