Isopropanol → 3-Bromo-5-(propan-2-yloxy)pyridine

Temperature

0 °C

Under a nitrogen atmosphere, 2-propanol (30 mL) was added to potassium (2.4 g, 61.4 mmol) at 0° C., and the mixture was stirred at 0° C. for 30 min. To the resulting solution was added 3,5-dibromopyridine (4.74 g, 20.0 mmol) and copper powder (250 mg, 3.9 mmol). The mixture was heated under reflux under a nitrogen atmosphere for 70 h. Upon cooling to ambient temperature, the mixture was concentrated under high vacuum to a solid, which was diluted with water (200 mL) and extracted with diethyl ether (3×150 mL). The combined ether extracts were dried (Na2SO4), filtered, and concentrated by rotary evaporation to a dark-brown oil (3.71 g). Purification by column chromatography on silica gel, eluting with 10→20% (v/v) diethyl ether in benzene afforded 1.38 g (31.9%) of 3-bromo-5-isopropoxypyridine as a volatile, colorless oil.

1. temperatureThe mixture was heated
2. temperatureunder reflux under a nitrogen atmosphere for 70 h
3. temperatureUpon cooling to ambient temperature
4. concentrationthe mixture was concentrated under high vacuum to a solid, which
5. additionwas diluted with water (200 mL)
6. extractionextracted with diethyl ether (3×150 mL)
7. dry with materialThe combined ether extracts were dried (Na2SO4)
8. filtrationfiltered
9. concentrationconcentrated by rotary evaporation to a dark-brown oil (3.71 g)
10. customPurification by column chromatography on silica gel
11. washeluting with 10→20% (v/v) diethyl ether in benzene

ORD record

ord-503c048ba54f4a69a22d8ff50c92ee29

Source dataset

uspto-grants-1999_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05861423