Iodine → 2-Amino-5-chloro-3-iodopyridine

Iodine (13.2 g, 52 mmol) was added to a mixture of 5-chloro-2-pyridinamine (6.68 g, 52 mmol) and silver sulfate (16.2 g, 52 mmol) in ethanol (350 mL) and the mixture was stirred at room temperature for 20 h. The mixture was filtered through a glass fibre pad and the solvent was evaporated under reduced pressure. The residue was dissolved in dichloromethane (600 mL), washed with aqueous sodium hydroxide (5%, 500 mL), water (500 mL) and brine (500 mL), dried (Na2SO4) and the solvent was evaporated under reduced pressure. The residue was purified by flash column chromatography on silica gel, eluting with isohexane/EtOAc (80:20), to give the title compound as a pale orange solid (7.1 g, 54%). 1H NMR (360 MHz, CDCl3) δ 7.99 (1H, d, J 2.2 Hz), 7.84 (1H, d, J 2.2 Hz), and 4.94 (2H, br s). m/z (ES+) 255, 257 (M+1).

1. filtrationThe mixture was filtered through a glass fibre pad
2. customthe solvent was evaporated under reduced pressure
3. dissolutionThe residue was dissolved in dichloromethane (600 mL)
4. washwashed with aqueous sodium hydroxide (5%, 500 mL), water (500 mL) and brine (500 mL)
5. dry with materialdried (Na2SO4)
6. customthe solvent was evaporated under reduced pressure
7. customThe residue was purified by flash column chromatography on silica gel
8. washeluting with isohexane/EtOAc (80:20)

ORD record

ord-0d8836b5e5374e23a46bab9c538aad53

Source dataset

uspto-grants-2002_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06476045B2