Hydrogen Bromide → 3-Bromo-2-chloro-4,6-dimethylpyridine

Temperature

0 °C

2-chloro-4,6-dimethylpyridin-3-amine (2.85 g) was dissolved in hydrobromic acid (15 mL, 48% aqueous solution), and the solution was cooled to 0° C. A solution of sodium nitrite (1.51 g) in water (2 mL) was slowly added dropwise to the solution, and the mixture was stirred at 0° C. for 15 minutes. A suspension of copper(I) bromide (4.18 g) in hydrobromic acid (5 mL, 48% aqueous solution) was added dropwise to the solution, and the mixture was stirred at 0° C. for 10 minutes and then at 60° C. for one hour. The reaction mixture was cooled to room temperature, followed by extraction with ethyl acetate. The organic layer was directly subjected to an NH-silica gel pad and eluted with ethyl acetate. The resulting solution was concentrated under reduced pressure, and the residue was purified by NH silica gel column chromatography (ethyl acetate/n-heptane, 0% to 30%) to give the title compound (2.97 g).

1. additionwas added dropwise to the solution
2. stirringthe mixture was stirred at 0° C. for 10 minutes
3. waitat 60° C. for one hour
4. temperatureThe reaction mixture was cooled to room temperature
5. extractionfollowed by extraction with ethyl acetate
6. washeluted with ethyl acetate
7. concentrationThe resulting solution was concentrated under reduced pressure
8. customthe residue was purified by NH silica gel column chromatography (ethyl acetate/n-heptane, 0% to 30%)

ORD record

ord-fe12ebb5089c49c89f934503d0ab48dc

Source dataset

uspto-grants-2013_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08563565B2