反应详情

温度

0 °C

A solution of the diacetate (17) (0.08 g, 0.21 mmol) in ethanol (5 mL) and THF (3 mL) was cooled to 0° C. in an ice bath. A solution of sodium borohydride (0.05 g, 1.32 mmol) in ethanol/water (10:3, 5 mL) was cooled to 0° C. in an ice bath and added to the steroid solution. The reaction mixture was stirred at 0° C. for 1 h., then allowed to warm to room temperature and stirred overnight. After that time, the reaction was diluted with water (20 mL) and neutralized with glacial acetic acid. The organic solvents were removed in vacuo under a stream of nitrogen, the residue was diluted with water (50 mL) and extracted with methylene chloride (3×). The organic fractions were washed with water (2×), brine (1×), filtered through sodium sulfate, combined and concentrated in vacuo. The residue was triturated with ether to give the pure product (18) (0.035 g, 55.7%.

1. temperatureto warm to room temperature
2. stirringstirred overnight
3. customThe organic solvents were removed in vacuo under a stream of nitrogen
4. additionthe residue was diluted with water (50 mL)
5. extractionextracted with methylene chloride (3×)
6. washThe organic fractions were washed with water (2×), brine (1×)
7. filtrationfiltered through sodium sulfate
8. concentrationconcentrated in vacuo
9. customThe residue was triturated with ether