反应详情

温度

-78 °C

A DCM (0.5 mL) slurry of lithium aluminum hydride (23 mg, 0.61 mmol, 2 equiv.) was cooled to −78° C. in a 10-mL recovery flask, and a DCM (0.5 mL) solution of 7 (106 mg, 0.31 mmol, 1 equiv.) was added via cannula, followed by a DCM (0.5 mL) rinse. The slurry was stirred at −78° C. for 25 min, Et2O (0.5 mL), and the reaction was warmed to 0° C. After stirring for 75 min, the reaction was quenched sequentially with H2O (23 μL), 15 wt % NaOHaq (23 μL), and H2O (63 μL). The reaction was then warmed to room temperature, diluted with H2O, and extracted four times with EtOAc. The organic extracts were combined, washed with H2O and brine, dried over Na2SO4, filtered, and concentrated in vacuo to a brown residue. Flash column chromatography (30 mL SiO2, 19:1 hexane:EtOAc) afforded 45 mg (0.14 mmol, 44% yield) of 8 as a clear, colorless oil. TLC Rf 0.74 (1:1 hexane:EtOAc). 1H NMR (600 MHz; CDCl3): δ 5.57 (ddt, J=17.1, 10.1, 7.1 Hz, 1H), 5.05 (t, J=7.2 Hz, 1H), 4.94-4.88 (m, 2H), 4.80 (t, J=3.5 Hz, 1H), 4.76 (t, J=3.5 Hz, 1H), 3.54 (s, 3H), 3.49 (s, 3H), 2.78 (app q, J=3.5 Hz, 2H), 2.64 (dd, J=8.0, 4.0 Hz, 1H), 2.39 (qd, J=12.7, 7.2 Hz, 2H), 2.03 (dd, J=13.7, 4.0 Hz, 1H), 1.97 (q, J=7.9 Hz, 2H), 1.76 (dd, J=13.7, 8.0 Hz, 1H), 1.67 (s, 3H), 1.58 (s, 3H), 1.57-1.54 (m, 1H), 1.29 (dt, J=13.5, 8.4 Hz, 1H), 1.18 (s, 3H). 13C NMR (125 MHz; CDCl3): δ 153.80, 153.73, 135.3, 131.8, 124.2, 116.1, 93.23, 93.17, 61.25, 61.09, 54.6, 54.2, 46.2, 40.2, 39.4, 34.2, 25.8, 24.2, 24.0, 17.8, 16.8. IR (NaCl, thin film, cm−1) 2932, 2831, 1694, 1659, 1451, 1381, 1223, 1206, 1139, 908. HRMS-ESI (m/z): [M+H]+ calculated for C21H32O3, 333.2424. found, 333.2425.

1. washrinse
2. temperatureEt2O (0.5 mL), and the reaction was warmed to 0° C
3. stirringAfter stirring for 75 min
4. customthe reaction was quenched sequentially with H2O (23 μL), 15 wt % NaOHaq (23 μL), and H2O (63 μL)
5. temperatureThe reaction was then warmed to room temperature
6. additiondiluted with H2O
7. extractionextracted four times with EtOAc
8. washwashed with H2O and brine
9. dry with materialdried over Na2SO4
10. filtrationfiltered
11. concentrationconcentrated in vacuo to a brown residue