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.
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].
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
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.
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
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.]
Acute toxicity:Harmful if swallowed.
Toxic in contact with skin.
LD50 Oral:1144 mg/kg, LD50 Dermal:400-640 mg/kg.
[1] You J, et al. Effect of 1-Methylimidazole on CO2 Absorption by Diethylenetriamine (DETA) Aqueous Solutions. Chemical Engineering & Technology, 2017; 40: 2238-2242.