反应详情

温度

5 °C

To a cooled solution of Intermediate 90 (2.2 g, 10.3 mmol) in methanol (30 mL) was added sodium borohydride (1.94 g, 51 mmol). The mixture was stirred at 5° C. for 20 minutes and at room temperature for 2 hours. To the crude reaction was added water (1 mL) and the solvents reduced under reduced pressure. The residue was dissolved in ethyl acetate (50 mL) and washed with brine (2×25 mL), dried (Na2SO4), and concentrated. Purification by column chromatography with silica gel eluting with ethyl acetate/n-hexane 1:5 gave the title compound (0.75 g, 42%) as oil.

1. customTo the crude reaction
2. washwashed with brine (2×25 mL)
3. dry with materialdried (Na2SO4)
4. concentrationconcentrated
5. customPurification by column chromatography with silica gel eluting with ethyl acetate/n-hexane 1:5