1698293-93-4

In a reaction vessel, 720 ml of 20% fuming sulfuric acid and 140 g of 2-isopropyl-4-methylpyridine were added. The temperature was raised to 160°C, and 250 g of bromine was slowly added dropwise. The reaction was carried out at 160-170°C for 15 hours. The reaction solution was cooled to room temperature and poured into ice water. The pH was adjusted to 10-11 with sodium carbonate. Steam distillation was performed to obtain 171 g of 3-bromo-4-methylpyridine (66% yield). In a high-pressure reaction vessel, 300 ml of methanol, 150 g of 3-bromo-4-methylpyridine, and 5 g of copper sulfate were added. Ammonia gas was introduced until the pressure reached 5 atm. The mixture was heated to 160°C and reacted for 8 hours. After cooling, the mixture was filtered, and the filtrate was concentrated under reduced pressure. The solid was recrystallized from ethyl acetate to obtain 89 g of 2-ISOPROPYL-4-METHYLPYRIDIN-3-AMINE (95% yield).