Ammonia → 2-Amino-4-bromo-5-chloro-3,6-difluoropyridine

Temperature

55 °C

To 20 ml of acetonitrile were added 4.9 g of 4-bromo-3-chloro-2,5,6-trifluoropyridine and 4 ml of 25% aqueous solution of ammonia, and the mixture was stirred at 55° C. for 2 hours. The solvent and the like were distilled off under reduced pressure. 50 ml of chloroform was added to the residue, and the solution was washed with 50 ml of distilled water. The chloroform layer was dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was dispersed in the mixed solution of diisopropylether and n-hexane and collected by filtration to obtain 3.8 g of the title compound as pale yellow needle crystals.

1. distillationThe solvent and the like were distilled off under reduced pressure
2. addition50 ml of chloroform was added to the residue
3. washthe solution was washed with 50 ml of distilled water
4. dry with materialThe chloroform layer was dried over anhydrous magnesium sulfate
5. concentrationconcentrated under reduced pressure
6. additionThe residue was dispersed in the mixed solution of diisopropylether and n-hexane
7. filtrationcollected by filtration

ORD record

ord-097e0494452043b59ef205ec4308aeda

Source dataset

uspto-grants-1999_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05998436