Reaction Steps
To a solution of 10 (812 mg, 1.68 mmol) in THF (80 mL) was added Hg(OAc)2 (534 mg, 1.68 mmol), and the mixture was stirred for 20 min at room temperature. K2CO3 (232 mg, 1.68 mmol) was then added, and the reaction mixture was stirred for 30 min, then cooled to -10° C. NaBH4 was added (420 g, 11.0 mmol), and the reaction was allowed to warm to room temperature and stir for an additional 15 min. Hexanes (20 mL) were then added, followed by brine (40 mL). The organic layer was separated, and the aqueous layer was extracted with EtOAc (2×25 mL). The combined organic layers were dried (MgSO4 ), concentrated under reduced pressure at room temperature, and then submitted to silica gel chromatography (solvent B) to give 11 (660 mg, 82%) as a glass: [α]D20 -41° (c 1.0, acetone); 1H NMR (CDCl3): δ -0.132, 0.256 (2s, 6H, --SiCH3), 0.792 [s, 9H, --C(CH3)3 ], 0.996 (t, 3H, J=7.3 Hz, CH2CH3), 1.05 (d, 3H, J=6.82 Hz, --CH3), 1.38 (d, 3H, J=6.35 Hz, --CH3 ), 1.45, 1.47 (2s, 6H, --C(CH3)2, 1.54-1.73 (m, 3H, H-11,-ch2 ch3), 2.87 (m, 2H, --CH2CH2CH3), 4.40 (m, 1H, H-10), 4.99 (d, H, J=2.1 Hz, H-12), 5.49 (d, 1H, J=10.0 Hz, H-7), 5.90 (s, 1H, H-3), 6.62 (d, 1H, J=10.0 Hz, H-8); 13C NMR (CDCl3): δ -0.91, -0.56, 13.89, 14.05, 18.46, 19.14, 23.10, 25.96, 27.75, 38.49, 39.02, 62.62, 72.91, 77.48, 102.77, 105.83, 106.75, 110.11, 116.63, 126.46, 151.18, 152.92, 153.05, 158.31, 160.54. Anal. Calcd for C28H40O5Si: C, 69.38; H, 8.32. Found C, 69.18; H, 8.25.
