反应详情

A solution of (7α,14β,15β,17α)-3-methoxy-7-methyl-14,15-methyleneestra-2,5(10)-diene-17-methanol (Example 1, step vi; 7.38 g) in a mixture of methanol (68 ml) and tetrahydrofuran (48 ml) was treated with a solution of oxalic acid (2.38 g) in water (40 ml). After 1 h stirring at room temperature, the reaction mixture was poured into a saturated aqueous solution of sodium hydrogencarbonate and the product was extracted into ethyl acetate. The combined organic phases were washed with brine, dried over sodium sulfate and concentrated under reduced pressure. Column chromatography afforded (7α,14β,15β,17α)-17-(hydroxyethyl)-7-methyl-14,15-methyleneestr-5(10)-en-3-one (4.27 g). 1H NMR (CDCl3) δ3.69 (m, 1H), 3.51 (t, 1H, J=9.0 Hz), 2.72 (bs, 2H), 2.46 (bs, 2H), 1.04 (s, 3H), 0.69 (d, 3H, J=7.1 Hz), 0.48(dd, 1H, J=8.3 and 5.1 Hz), 0.27 (dd, 1H, J=5.1 and 3.1 Hz).

1. extractionthe product was extracted into ethyl acetate
2. washThe combined organic phases were washed with brine
3. dry with materialdried over sodium sulfate
4. concentrationconcentrated under reduced pressure