反应详情

Acetic anhydride (0.17 mL, 1.8 mmol), then pyridine (90 μL, 1.1 mmol), were added sequentially to alcohol 7 (0.17 g, 0.93 mmol) in CH2Cl2 (1.8 mL), and stirred at room temperature for 17 hours. The mixture was diluted with diethyl ether, washed with saturated aqueous NaHCO3, then brine, dried with Na2SO4, and concentrated. Flash chromatography of the residue (SiO2, 5% EtOAc in hexanes) provided 8 (0.18 g, 87% yield, 74% Z as determined by 13C-NMR) as a colorless oil; 1H NMR (CDCl3): δ 5.28-5.43 (2H, m), 4.05 (2H, t, J=6.8 Hz), 2.04 (7H, m), 1.61 (2H, td, J=9.8, 8.7, 4.6 Hz), 1.29 (10H, m), 0.95 (3H, m); 13C NMR (CDCl3): δ 171.3, 131.6, 129.3, 64.7, 32.6, 29.8, 29.5, 29.3, 29.2, 28.7, 26.0, 21.1, 20.6, 14.5; HRMS (FAB): 227.2045, [C14H26O2+H]+ requires 227.2006.

1. washwashed with saturated aqueous NaHCO3
2. dry with materialbrine, dried with Na2SO4
3. concentrationconcentrated
4. customFlash chromatography of the residue (SiO2, 5% EtOAc in hexanes) provided 8 (0.18 g, 87% yield, 74% Z as determined by 13C-NMR) as a colorless oil