反应详情

To a solution of (3aR,4R,5R,6S,7aS)-6-(difluoromethyl)-4,5-dihydroxyhexahydrobenzo[d]oxazole-2(3H)-thione (233 mg, 0.97 mmol) in EtOH (5 mL) was added MeI (277 mg, 1.95 mmol) and 5 N NaOH (0.21 mL, 1.1 mmol). The mixture was stirred at room temperature for 2 h. The solvents were evaporated to give the crude product. This was purified by SiO2 column, eluted with 3%-5% MeOH in DCM to give (3aR,4R,5R,6S,7aS)-6-(difluoromethyl)-2-(methylthio)-3a,4,5,6,7,7a-hexahydrobenzo[d]oxazole-4,5-diol (218 mg, 88%) as a pale yellow solid. MS m/z 254.1 (M+1, 100%); 1H NMR (400 MHz, MeOD) δ 6.16 (td, J=56.8 Hz, 1.8 Hz, 1H), 4.79-4.83 (m, 1H), 3.85 (t, J=7.6 Hz, 1H), 3.39 (t, J=9.0 Hz, 1H), 3.28 (t, J=7.9 Hz, 1H), 2.48 (s, 3H), 2.27 (dt, J=14.7 Hz, 3.6 Hz, 1H), 1.91-2.10 (m, 2H).

1. customThe solvents were evaporated
2. customto give the crude product
3. customThis was purified by SiO2 column
4. washeluted with 3%-5% MeOH in DCM