反应详情

To a stirred solution of 5-bromo-4-chloropyridin-2-amine (11.6 g, 55.9 mmol) in pyridine (100 mL) at 0° C. was added acetyl chloride (3.98 mL, 55.9 mmol) and the reaction was stirred at rt for 3 hours. The reaction was quenched with cold water. The reaction mixture was concentrated under reduced pressure. The residue was reconstituted in ethyl acetate and water. The organics were extracted with ethyl acetate (3×50 mL). The combined organic layers were washed with water (100 mL), brine (100 mL) and dried over sodium sulfate. The organics were concentrated under reduced pressure to afford N-(5-bromo-4-chloropyridin-2-yl)acetamide as a white solid (14.6 g, 55.9 mmol, quantitative yield) that was used without further purification in the next step. LCMS (ESI) m/e 249 [(M+H)+, calcd for C7H7BrClN2O 248.9 LC/MS retention time (method B): tR=1.64 min; 1H NMR (400 MHz, DMSO-d6) δ 10.87 (s, 1H), 8.58 (s, 1H), 8.33 (s, 1H), 2.11 (s, 3H).

1. customThe reaction was quenched with cold water
2. concentrationThe reaction mixture was concentrated under reduced pressure
3. extractionThe organics were extracted with ethyl acetate (3×50 mL)
4. washThe combined organic layers were washed with water (100 mL), brine (100 mL)
5. dry with materialdried over sodium sulfate
6. concentrationThe organics were concentrated under reduced pressure