反应详情

A slurry of 3-amino-4-methoxy-6-nitrotoluene (18 g) in water (20 ml) containing acetic acid (20 ml) and hydrobromic acid (47%, 35 ml) is stirred until a fine suspension of the hydrobromide is formed, cooled to 0°, and treated with a solution of sodium nitrite (7 g) in water (20 ml) added over 20 min. After a further 10 min., the yellow-brown solution is stirred into a mixture of cuprous bromide (30 g) and hydrobromic acid (47%, 30 ml) in water (50 ml), the mixture warmed on the steam bath until an effervescence commences and then at 70° for 1 hr. The mixture is cooled, diluted with water (500 ml), and the solid collected and recrystallized from aqueous ethanol to give a 3-bromo-4-methoxy-6-nitrotoluene (I) as pale yellow needles (18 g, 72%): mp 91-92°.

1. customis formed
2. temperaturecooled to 0°
3. additionadded over 20 min
4. temperaturethe mixture warmed on the steam bath until an effervescence commences
5. waitat 70° for 1 hr
6. temperatureThe mixture is cooled
7. customthe solid collected
8. customrecrystallized from aqueous ethanol