Sodium Hydroxide → 5-Bromo-2-chloro-4-methoxypyridine

To a solution of 2-chloro-4-methoxypyridine (10.0 g, 69.7 mmol) in 50 mL of sulfuric acid at 0° C. was added NBS. The reaction mixture was allowed to stir and warm up to room temperature for 2 hour and then heated at 60° C. for 5 h. Then it was cooled to room temperature and neutralized with 1 N NaOH (pH ˜7), diluted with water (50 mL) and the aqueous layer was extracted with ethyl acetate (2×100 mL). The organic layers were washed with water (2×50 mL), sat. NaHCO3, brine, dried over Mg2SO4 and concentrated to provide an oil, which was chromatographed. On elution with 0-25% EtOAc/hexanes, of the final product was obtained. 1H NMR (500 MHz, DMSO-d6), δ 8.4 (s, 1H), 7.29 (s, 1H), 3.97 (s, 3H);

1. temperatureheated at 60° C. for 5 h
2. extractionthe aqueous layer was extracted with ethyl acetate (2×100 mL)
3. washThe organic layers were washed with water (2×50 mL), sat. NaHCO3, brine
4. dry with materialdried over Mg2SO4
5. concentrationconcentrated
6. customto provide an oil, which
7. customwas chromatographed
8. washOn elution with 0-25% EtOAc/hexanes

ORD record

ord-73acf9c9c2a2400fa5333be58d249796

Source dataset

uspto-grants-2014_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08673920B2