反应详情

温度

-50 °C

To a solution of compound 3 (100 mg, 0.38 mmol) in dimethoxyethane (DME, 7 mL) was added at −50° C., under argon, (diethylamino)sulfur trifluoride (DAST, 100 μL, 0.76 mmol). The mixture was stirred at −50° C. for 10 min and then at room temperature for 1.5 h. Dichloromethane (5 mL) and a saturated aqueous sodium carbonate solution (5 mL) were then successively added. The organic layer was dried on magnesium sulfate, filtered and evaporated under vacuum. The residue was chromatographed (SiO2, AcOEt/pentane, 1/1, v/v) to give compound 21 (51 mg, 0.19 mmol) as a white solid. Yield 50%; Rf (SiO2, AcOEt/pentane, 1/1, v/v) 0.53; mp 57-59° C.; IR (KBr) ν 1023, 1403, 1715, 1769, 2700-3000 cm−1; 1H NMR (200 MHz, CDCl3) δ 1.00 (t, 3H, J=7.1 Hz), 2.68 (q, 2H, J=7.1 Hz), 2.86 (m, 4H), 3.78 (t, 2H, J=6.6 Hz), 4.47 (td, 2H, 2JH-F=47.5 Hz, J=5.1 Hz), 7.70 (m, 2H), 7.83 (m, 2H); MS m/z 264 (M+, 1), 104 (100), 76 (38), 56 (18).

1. waitat room temperature for 1.5 h
2. customThe organic layer was dried on magnesium sulfate
3. filtrationfiltered
4. customevaporated under vacuum
5. customThe residue was chromatographed (SiO2, AcOEt/pentane, 1/1