反应详情

To a solution of compound 88 (150 mg, 0.71 mmol) in methanol (2 mL) was added a solution of hydroxylamine hydrochloride (74 mg, 1.07 mmol) and potassium acetate (105 mg, 1.07 mmol) in water (7 mL). The mixture was stirred at room temperature for 4 h and the methanol was then evaporated under reduce pressure. A saturated aqueous sodium chloride solution (10 mL) was added and the mixture was extracted with dichloromethane (4×20 mL). The organic layers were combined, dried on magnesium sulfate, filtered and evaporated under vacuum. The residue was chromatographed (Al2O3, AcOEt→AcOEt/EtOH, 85/15, vi/v) to give compound 89 (131 mg, 0.58 mmol) as a white solid. Yield 81%; Rf (Al2O3, AcOEt/EtOH, 85/15, v/v) 0.89; mp 97-99° C.; IR (KBr) ν 1264, 1331, 1392, 1605, 2750-2980, 3100, 3191 cm−1; 1H NMR (200 MHz, CDCl3) δ 1.05 (t, 6H, J=7.1 Hz), 2.57 (q, 4H, J=7.1 Hz), 3.83 (s, 2H), 7.56 (d, 1H, J=5.1 Hz), 8.13 (d, 1H, J=5.1 Hz), 8.43 (s, 1H); ESI-MS m/z 225.8 [M+H]+.

1. customthe methanol was then evaporated
2. additionA saturated aqueous sodium chloride solution (10 mL) was added
3. extractionthe mixture was extracted with dichloromethane (4×20 mL)
4. customdried on magnesium sulfate
5. filtrationfiltered
6. customevaporated under vacuum
7. customThe residue was chromatographed (Al2O3, AcOEt→AcOEt/EtOH, 85/15, vi/v)