反应详情

A solution of 3,3:17,17-bis(ethylendioxy)androstane-6α-yl nitrate (2.50 g) and pTSA.H2O (6.05 g) in acetone (150 mL) was stirred at room temperature for 1.5 h. The solution was neutralized by addition of 5% aqueous NaHCO3, and acetone was evaporated. The aqueous phase was extracted with CH2Cl2 (3×50 mL). The combined organic extracts were washed with H2O, dried over Na2SO4 and evaporated to dryness. The residue was purified by flash chromatography (SiO2, cyclohexane/acetone/CH2Cl2 70/15/15) to give the title compound II-aa as a white solid (1.66 g, 75%). 1H-NMR (300 MHz, acetone-d6, ppm from TMS): δ 5.09 (ddd, 1H), 2.60-0.95 (m, 17H), 1.25 (s, 3H), 0.90 (s, 3H).

1. customwas evaporated
2. extractionThe aqueous phase was extracted with CH2Cl2 (3×50 mL)
3. washThe combined organic extracts were washed with H2O
4. dry with materialdried over Na2SO4
5. customevaporated to dryness
6. customThe residue was purified by flash chromatography (SiO2, cyclohexane/acetone/CH2Cl2 70/15/15)