反应详情

A solution of 2-amino-3-bromo-5-chloropyridine (4.0 g, 19.3 mmol) in water (30 mL) and conc. HCl (5.2 mL) was cooled with an ice bath to 0° C. and was treated with a solution of sodium nitrite (1.33 g, 19.3 mmol) in water (12 mL) over 10 min. The mixture was stirred for an additonal 10 min and allowed to warm to room temperature over 48 hr. The mixture was filtered. The solids were washed with water, then with CCl4 and were dried under vacuum at 50° C. for 3 hr to give 3-bromo-5-chloro-1H-2-pyridone (2.77 g, 69%), mp 173.5-175° C.

1. filtrationThe mixture was filtered
2. washThe solids were washed with water
3. dry with materialwith CCl4 and were dried under vacuum at 50° C. for 3 hr