反应详情

7.97 g (35.4 mmol, 1 eq) of 3-bromo-1,5-naphthyridine-5-oxide and 9.9 mL (106.2 mmol, 3 eq) of phosphorus oxychloride were introduced in 600 mL of methylene chloride. The mixture was stirred at reflux for 18 h. Methylene chloride was evaporated in part (¾). 1M aqueous NaOH solution was added carefully at 0° C. Aqueous layer was extracted with methylene chloride. Organic layers were dried over Na2SO4, filtered and evaporated to dryness. The residue was purified by column chromatography using methylene chloride as eluent. The solvent was evaporated to dryness to afford 1.97 g of 7-bromo-2-chloro-1,5-naphthyridine (white powder) with 22% yield and 4.16 g of 7-bromo-4-chloro-1,5-naphthyridine (white powder) with 48% yield.

1. temperatureat reflux for 18 h
2. customMethylene chloride was evaporated in part (¾)
3. addition1M aqueous NaOH solution was added carefully at 0° C
4. extractionAqueous layer was extracted with methylene chloride
5. dry with materialOrganic layers were dried over Na2SO4
6. filtrationfiltered
7. customevaporated to dryness
8. customThe residue was purified by column chromatography
9. customThe solvent was evaporated to dryness