反应详情

1.32 g 2-amino-1H-imidazol-hemisulfate is diazotized in a mixture containing 2 ml hydrochloric acid, 2 ml acetic acid, 12 ml water and 0.7 g sodium nitrate at 5° C. Azo coupling is performed by adding 2.3 g N-(2-bromoethyl)-N-ethylaniline to the above diazonium solution. After stirring for 2 hours at room temperature the mixture is poured on 50 ml saturated sodium bicarbonate. The resulted precipitate is filtered off, washed with water, and dried in vacuum at 40° C. After chromatography on silicagel with ethylacetate, 0.6 g N-(2-bromoethyl)-N-ethyl-4-[(E)-1H-imidazol-2-yldiazenyl]aniline is obtained as a brown powder.

1. filtrationThe resulted precipitate is filtered off
2. washwashed with water
3. customdried in vacuum at 40° C