Sodium Hydroxide → 3-Amino-6-bromopyrazine-2-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

Methy 3-amino-6-bromopyrazine-2-carboxylate (1.4 Kg), 5N NaOH solution (5.6 L) and methanol (8.4 L) were charged into reactor. The resulting suspension was warmed at 50° C. for 3 hours with vigorous stirring. The mixture was analysed for reaction completion. The mixture was cooled to 25° C. and the solids were collected by filtration. Filter cake was washed with water (1 L). The resultant solids were suspended in water (5 L) and pH value of this suspension was adjusted to 3 by adding 6 N HCl solution. The acidic solution was vigorously stirred at 25° C. for 48 h. During this period, pH value was checked, additional acid was charged if pH value >3. The suspension was filtered to collect a yellow-brown solid, which was dried in oven at 40° C. under a flow of N2. The crude subtitle material was used in the next step.

Provenance & Evidence