Cl(O)(=O)(=O)=O.[CH3:6][C@H:7]1[C:11](=[O:12])[O:10][C@@H:9]2[CH2:13][CH:14]=[CH:15][C@H:8]12.[OH-:16].[Na+].[BH4-].[Na+].Cl.[Na+].[Cl-]>C1COCC1.O.C1COCC1.[Hg](OC(C)=O)OC(C)=O>[OH:16][C@H:14]1[CH2:13][C@H:9]2[O:10][C:11](=[O:12])[C@H:7]([CH3:6])[C@H:8]2[CH2:15]1To a ice-cold yellow solution of Hg(OAc)2 (1.45 g, 4.57 mmol) in THF:H2O (2.5:1 ratio, 23 mL) was added perchloric acid (˜0.7 mL) until the solution became colorless. A solution of lactone 116 (350 mg, 2.54 mmol) in THF (7 mL) was then added at 0° C. and the reaction was stirred for 1 h. Additional Hg(OAc)2 (646 mg, 2.03 mmol) similarly pretreated with perchloric acid in THF:H2O (2.5:1, 10 mL) was added and stirring was continued for 2 h at 0° C. The pH of the mixture was then adjusted to ˜10 by addition of a 1M aqueous NaOH solution. Stirring was then continued for 1 h at room temperature. The solution was cooled to 0° C. and NaBH4 (145 mg, 3.81 mmol) was added in small portions. After 1 h, the reaction mixture was acidified to pH=2 with concentrated HCl and stirring was continued for 1 h. The reaction solution was saturated with NaCl, and the aqueous phase extracted several times with EtOAc. The combined organic phase was dried (Na2SO4), filtered, and concentrated under vacuum. The residue was purified by column chromatography on silica gel using 2% MeOH in CH2Cl2 to yield alcohol 117 (252 mg, 64%) as a colorless oil. TLC: Rf=0.31 (CHCl3/MeOH=9/1); [α]D20+53.5 (c 1.0, CHCl3); 1H NMR (CDCl3, 400 MHz) δ 4.98 (dt, J=8.0, 14.9 Hz, 1H), 4.55 (m, 1H), 2.69 (qd, J=3.9, 7.6 Hz, 1H), 2.58 (m, 1H), 2.55 (m, 1H), 2.09 (d, J=15.0 Hz, 1H), 1.94 (m, 2H), 1.83 (m, 1H), 1.26 (d, J=7.6 Hz, 3H); 13C NMR (CDCl3, 100 MHz) δ 181.0, 83.8, 74.6, 51.2, 45.5, 43.9, 41.3, 18.4.
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