Hydroxylamine → 4-(7-Bromo-4-chloro-1-ethyl-1H-imidazo[4,5-c]pyridin-2-yl)-1,2,5-oxadiazol-3-amine

Participants

Reaction Conditions

Reaction Steps

To a mixture of (7-bromo-4-chloro-1-ethyl-1H-imidazo[4,5-c]pyridin-2-yl)hydroxyimino-acetonitrile (V, 545 g, 1.45 mol) in dioxane (5 L) was added triethylamine (1 L) and hydroxylamine (143 g, 55% in water). The reaction was heated at reflux for 6 h. After cooling the reaction to ambient temperature, the mixture was filtered and the filtrate concentrated under reduced pressure to give a brown solid. The solid was suspended in methanol (1 L) and the suspension was stirred at 65° C. for 0.5 h. The solid was collected by filtration and dried to give 321 g (70% yield) of the desired compound (VI). This was used in the next step without further purification. MS (ES+) m/z 343 (M+H)+.

Provenance & Evidence