Ammonium Hydroxide → 5-Methoxypyridin-3-ylamine

Temperature

171 °C

Crude 5-bromo-3-methoxypyridine (3.50 g, 18.62 mmol) was dissolved in methanol (50 mL) and added to concentrated ammonium hydroxide (29.7%, 14.8 M, 50 mL) and copper(I) bromide (2.67 g, 18.62 mmol) in a heavy-walled glass pressure-tube apparatus. The tube was flushed with nitrogen and sealed. The mixture was stirred and heated at 170-172° C. (oil bath temperature) for 24 h. After cooling, the solution was concentrated by rotary evaporation to a gummy residue. The residue was diluted with sodium carbonate solution (17.6%, 200 mL) and extracted with CH2Cl2 (4×50 mL). The combined CH2Cl2 extracts were dried (MgSO4), filtered, and concentrated by rotary evaporation to give 1.26 g of a cream-brown solid. The aqueous phase was re-extracted with CH2Cl2 (4×50 mL). The combined CH2Cl2 extracts were similarly dried and concentrated to give an additional 0.34 g of a cream-brown solid, bringing the total yield to 1.60 g (69.2%).

1. customThe tube was flushed with nitrogen
2. customsealed
3. temperatureAfter cooling
4. concentrationthe solution was concentrated by rotary evaporation to a gummy residue
5. additionThe residue was diluted with sodium carbonate solution (17.6%, 200 mL)
6. extractionextracted with CH2Cl2 (4×50 mL)
7. dry with materialThe combined CH2Cl2 extracts were dried (MgSO4)
8. filtrationfiltered
9. concentrationconcentrated by rotary evaporation

ORD record

ord-8c82d09033c04f8e96ce9d5088b380d8

Source dataset

uspto-grants-2002_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06441006B2