Stannous Chloride → 3-Amino-5-bromo-2-chloropyridine

To a solution of 5-bromo-2-chloro-3-nitropyridine (4.24 g, 17.86 mmol) in EtOH (89 ml) was added Tin(II) chloride (16.9 g, 89.0 mmol) at room temperature. The mixture was refluxed for 1 hour, and then cooled to room temperature, filtered through a Celite pad and washed with EtOAc. The filtrate was concentrated in vacuo. The residue was treated with saturated aq. NaHCO3, and extracted with EtOAc. The combined organic layers were washed brine, dried over anhydrous Na2SO4, filtered and concentrated in vacuo. The residue was purified by column chromatography on SiO2 (Hex:EtOAc=3:1) to give 5-bromo-2-chloropyridin-3-amine (2.7 g, 73%) as a white solid. 1H-NMR (CDCl3, Varian 400 MHz) δ 5.89 (2H, brs), 7.30 (1H, d, J=2.0 Hz), 7.66 (1H, d, J=2.4 Hz).

1. temperatureThe mixture was refluxed for 1 hour
2. filtrationfiltered through a Celite pad
3. washwashed with EtOAc
4. concentrationThe filtrate was concentrated in vacuo
5. additionThe residue was treated with saturated aq. NaHCO3
6. extractionextracted with EtOAc
7. washThe combined organic layers were washed brine
8. dry with materialdried over anhydrous Na2SO4
9. filtrationfiltered
10. concentrationconcentrated in vacuo
11. customThe residue was purified by column chromatography on SiO2 (Hex:EtOAc=3:1)

ORD record

ord-ebc1ae4c43d34747904d7b62810753c9

Source dataset

uspto-grants-2014_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08664230B2