反应详情

To alcohol 5b (600 mg, 1.67 mmol) dissolved in 85 mL of methylene chloride was added Dess-Martin periodinane (DMP, 1.41 g, 3.34 mmol), and the mixture was allowed to stir at room temperature for 1.5 hours. Upon reaction completion, saturated aqueous NaHCO3 (50 mL) was added and the aqueous phase was extracted 3 times with methylene chloride (3×50 mL). The organic extracts were then combined, dried with MgSO4, and concentrated. The crude mixture was purified using flash chromatography (hexanes:ethyl acetate 7:1) to give 6b (476 mg, 1.34 mmol, 80% yield) as a white crystalline solid. 1H NMR (400 MHz, CDCl3) δ 6.41 (s, 1H), 6.27 (s, 1H), 3.77 (s, 3H), 3.75 (s, 3H), 2.71-2.65 (m, 1H), 2.64-2.56 (m, 2H), 2.54-2.41 (m, 2H), 1.87-1.81 (m, 1H), 1.78-1.73 (m, 2H), 1.71-1.48 (m, 4H), 1.13 (s, 3H), 1.11 (s, 6H), 1.09 (s, 3H); 13C NMR (100 MHz, CDCl3) δ217.2, 159.5, 155.8, 144.4, 132.9, 101.9, 96.8, 63.4, 55.4, 55.3, 54.9, 47.5, 45.8, 38.8, 37.4, 36.2, 33.9, 29.5, 26.5, 20.7, 20.5, 19.8, 15.5. ESIMS [M+Na]+ calcd for C23H32O3Na 379.2249, found 379.2243. [α]24D=+26.78°.

1. additionwas added
2. extractionthe aqueous phase was extracted 3 times with methylene chloride (3×50 mL)
3. dry with materialdried with MgSO4
4. concentrationconcentrated
5. customThe crude mixture was purified