反应详情

To a stirred solution of 1.0 M lithium aluminium hydride in anhydrous tetrahydrofuran (7.00 mL, 7.00 mmol) was added at −50° C., under argon, a solution of compound 28 (1.19 g, 7.00 mmol) in anhydrous tetrahydrofuran (10 mL). After 15 min, water (7 mL), a 3.0 N aqueous sodium hydroxide solution (7 mL) and water (7 mL) were added successively to the mixture until no more gas evolution was observed. After return back to room temperature, a brine solution (10 mL) was added. The mixture was extracted with dichloromethane (3×10 mL). The organic layers were combined, dried on magnesium sulfate, filtered and evaporated under reduced pressure. The residue was chromatographed (Al2O3, CH2Cl2) to give compound 29 (0.45 g, 3.50 mmol) as a beige solid. Yield 51%; Rf (Al2O3, CH2Cl2) 0.32; mp 61-63° C.; IR (KBr) ν 1074, 1273, 1420, 1618, 3100-3400 cm−1; 1H NMR (200 MHz, CDCl3) δ 3.81 (se, 1H), 4.75 (s, 2H), 6.96 (s, 1H), 7.14 (m, 1H), 8.07 (d, 1H, J=5.1 Hz).

1. extractionThe mixture was extracted with dichloromethane (3×10 mL)
2. customdried on magnesium sulfate
3. filtrationfiltered
4. customevaporated under reduced pressure
5. customThe residue was chromatographed (Al2O3, CH2Cl2)