反应详情

To a stirred solution of 0.95 g (7.48 mmol) of 3-fluoro-4-methylpyridine N-oxide 5-2 in 20 mL of acetonitrile was added 1.14 g (11.2 mmol) of triethylamine followed by 1.48 g (15.0 mmol) of trimethylsilyl cyanide. This reaction mixture was heated at reflux for 48 h, after which time the solution was concentrated at reduced pressure. The dark residue was dissolved in CHCl3, washed with saturated aqueous NaHCO3 and the aqueous layer back-washed with chloroform (4×). The combined organic layers were dried over MgSO4 and the solvents removed at reduced pressure to give an oil that was chromatographed on SiO2 using 75:25 hexane-EtOAc to give 5-3 as a yellow oil: 1H NMR (CDCl3) δ 8.39 (d, 1H, 4.8 Hz), 7.09 (br dd, 1H, 5.8, 5.8 Hz), 2.41 (s, 3H).

1. temperatureThis reaction mixture was heated
2. temperatureat reflux for 48 h
3. concentrationafter which time the solution was concentrated at reduced pressure
4. dissolutionThe dark residue was dissolved in CHCl3
5. washwashed with saturated aqueous NaHCO3
6. washthe aqueous layer back-washed with chloroform (4×)
7. dry with materialThe combined organic layers were dried over MgSO4
8. customthe solvents removed at reduced pressure
9. customto give an oil that
10. customwas chromatographed on SiO2 using 75:25 hexane-EtOAc