反应详情

A 250-mL Parr reactor bottle was purged with nitrogen and charged with 10% palladium on carbon (50% wet, 100 mg dry weight) and a solution of 121a (500 mg, 1.55 mmol) in ethanol (20 mL). The bottle was attached to Parr hydrogenator, evacuated, charged with hydrogen gas to a pressure of 45 psi and shaken for 4 h. After this time, the hydrogen was evacuated, and nitrogen was charged into the bottle. Celite 521 (1.0 g) was added, and the mixture was filtered through a pad of Celite 521. The filter cake was washed with ethanol (2×30 mL), and the filtrate was concentrated under reduced pressure to afford a 95% yield of 121b (430 mg) as an amber film: 1H NMR (500 MHz, CDCl3) δ 7.98 (d, 1H, J=2.5 Hz), 7.38 (dd, 1H, J=8.5, 2.0 Hz), 6.52 (d, 1H, J=8.5 Hz), 4.54 (s, 1H), 4.26 (s, 2H), 3.78 (t, 2H, J=5.5 Hz), 3.67 (t, 2H, J=5.0 Hz), 1.50 (s, 9H); MS (ESI+) m/z 293.1 (M+H).

1. customA 250-mL Parr reactor bottle was purged with nitrogen
2. additioncharged with 10% palladium on carbon (50% wet, 100 mg dry weight)
3. customevacuated
4. additioncharged with hydrogen gas to a pressure of 45 psi
5. customAfter this time, the hydrogen was evacuated
6. additionnitrogen was charged into the bottle
7. additionCelite 521 (1.0 g) was added
8. filtrationthe mixture was filtered through a pad of Celite 521
9. washThe filter cake was washed with ethanol (2×30 mL)
10. concentrationthe filtrate was concentrated under reduced pressure