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 lookchem 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.

Hazard

Possible carcinogen.

Flammability and Explosibility

Notclassified

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.]

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.