反应详情

Potassium metal (6.59 g, 168.84 mmol) was dissolved in dry 2-propanol (60.0 mL) under nitrogen. The resulting potassium isopropoxide was heated with 3,5-dibromopyridine (20.00 g, 84.42 mmol) and copper powder (1 g, 5% by weight of 3,5-dibromopyridine) at 140° C. (oil bath temperature) in a sealed glass tube for 14 h. The reaction mixture was cooled to ambient temperature and extracted with diethyl ether (4×200 mL). The combined ether extracts were dried over sodium sulfate, filtered, and concentrated by rotary evaporation. The crude product obtained was purified by column chromatography over aluminum oxide, eluting with ethyl acetate-hexane (1:9, v/v). Selected fractions were combined and concentrated by rotary evaporation, producing a pale-yellow oil (12.99 g, 71.2%).

1. extractionextracted with diethyl ether (4×200 mL)
2. dry with materialThe combined ether extracts were dried over sodium sulfate
3. filtrationfiltered
4. concentrationconcentrated by rotary evaporation
5. customThe crude product obtained
6. customwas purified by column chromatography over aluminum oxide
7. washeluting with ethyl acetate-hexane (1:9, v/v)
8. concentrationconcentrated by rotary evaporation