Iodine chloride → 4-Ethyl-5-iodopyridin-2-amine

Temperature

80 °C

4-ethyl-2-aminopyridine (10.0 g, 81.9 mmol) and potassium acetate (8.00 g, 81.9 mmol) were dissolved in 100 mL of acetic acid and heated to 80° C. with continuous stirring. In a separate flask, iodomonochloride (13.2 g, 81.9 mmol) was dissolved in 30 mL of acetic acid and added to the above reaction mixture drop wise. Once the addition was completed, the reaction mixture was heated for an additional 4 h. Progress of the reaction was monitored by gas chromatography and HPLC. When the reaction was completed, the reaction mixture was cooled to room temperature and quenched with an aqueous solution of saturated sodium bisulfite (10 mL). Acetic acid was removed under vacuum and the residue was dissolved in ethyl acetate and neutralized with saturated NaHCO3. The organic layer was separated from the aqueous layer and the solvent was removed under vacuum. The crude was purified by silica gel column chromatography eluting with 25% ethyl acetate/hexanes. 15 g of desired product was obtained (74% yield).

1. additionadded to the above reaction mixture drop wise
2. additionOnce the addition
3. temperaturethe reaction mixture was heated for an additional 4 h
4. temperaturethe reaction mixture was cooled to room temperature
5. customquenched with an aqueous solution of saturated sodium bisulfite (10 mL)
6. customAcetic acid was removed under vacuum
7. dissolutionthe residue was dissolved in ethyl acetate and neutralized with saturated NaHCO3
8. customThe organic layer was separated from the aqueous layer
9. customthe solvent was removed under vacuum
10. customThe crude was purified by silica gel column chromatography
11. washeluting with 25% ethyl acetate/hexanes

ORD record

ord-a418b6dc4a5c40e49e0fdb6f14dec7e9

Source dataset

uspto-grants-2013_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08519384B2