反应详情

温度

0 °C

To a solution of 17A (1.33 g, 6.09 mmol) in THF (20 mL) at 0° C., was added lithium borohydride (0.531 g, 24.36 mmol). The resultant suspension was stirred at rt for 7 h. The reaction was cooled to 0° C., then was quenched with sat. NH4Cl (5 mL). The mixture was diluted with H2O and hexanes. The reaction mixture was acidified with 1 N HCl, then was extracted with hexanes (3×). The combined organic phase was washed with brine, dried (Na2SO4), and concentrated. The crude product was purified by flash chromatography (0 to 60% ethyl acetate/hexanes) to give 17B (980 mg, 5.15 mmol, 85% yield) as a colorless oil. MS (ESI) m/z: 191.2 [M+1]+. 1H NMR (400 MHz, chloroform-d) δ ppm 3.87-3.96 (m, J=6.3, 6.3, 6.3, 6.3, 3.6 Hz, 1H) 3.51 (ddd, J=11.0, 7.7, 3.6 Hz, 1 H) 3.37 (ddd, J=11.1, 6.3, 5.1 Hz, 1H) 1.93 (dd, J=7.8, 5.3 Hz, 1H) 1.12 (d, J=6.3 Hz, 3H) 0.90 (s, 9H) 0.09 (s, 6H).

1. customwas quenched with sat. NH4Cl (5 mL)
2. additionThe mixture was diluted with H2O and hexanes
3. extractionwas extracted with hexanes (3×)
4. washThe combined organic phase was washed with brine
5. dry with materialdried (Na2SO4)
6. concentrationconcentrated
7. customThe crude product was purified by flash chromatography (0 to 60% ethyl acetate/hexanes)