METHOD FOR PREPARING 2-METHYLIMIDAZOLE Russian patent published in 2013 - IPC C07D233/56 

FIELD: medicine, pharmaceutics.

SUBSTANCE: present invention refers to a method for preparing 2-methylimidazole involving mixing 40% aqueous glyoxal, acetaldehyde and aqueous ammonia, further recovering an end product by distillation, differing by the fact using 25% ammonia, mixing acetaldehyde and ammonia at temperature 0÷5°C; adding glyoxal preliminary purified from impurities by electrodialysis at temperature no more than 60°C; the agents taken in a ratio of ammonia : acetaldehyde : glyoxal = 2:1:1; the reaction conducted at temperature 90-95°C for 3 hours; besides, the end product recovered by vacuum distillation at residual pressure 0.5-1.5 kPa and vapour temperature 120-140°C preceded by water distillation.

EFFECT: what is developed is the new method for preparing 2-methylimidazole differing by high yield and end product quality, as well as simplified process of recovering and purifying.

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