C(NC(C)C)(C)C.[Li]CCCC.[C:13]([O:16][CH3:17])(=[O:15])[CH3:14].[C:18]1([C:27]2[CH:32]=[CH:31][CH:30]=[CH:29][CH:28]=2)[CH:23]=[CH:22][C:21]([CH2:24][CH:25]=[O:26])=[CH:20][CH:19]=1>C1COCC1>[C:18]1([C:27]2[CH:28]=[CH:29][CH:30]=[CH:31][CH:32]=2)[CH:19]=[CH:20][C:21]([CH2:24][CH:25]([OH:26])[CH2:14][C:13]([O:16][CH3:17])=[O:15])=[CH:22][CH:23]=1A solution of diisopropylamine (0.241 mL, 1.72 mmol) in anhydrous THF (1.5 mL) was treated with n-BuLi (1.6 M in hexane, 0.7 mL, 1.72 mmol) at −78° C. The mixture was kept at this temperature for 1 h, and then a solution of methyl acetate (0.137 mL, 1.72 mmol) in anhydrous THF (1 mL) was added at −78° C. The reaction mixture was stirred for 1 h at −78° C., and a solution of 2-(biphenyl-4-yl)acetaldehyde (S90, 282 mg, 1.43 mmol) in anhydrous THF (2 mL) was added. The reaction mixture was stirred for another hour, then quenched by the addition of saturated aqueous NH4Cl, which was extracted with EtOAc. The combined extracts were dried over Na2SO4 and the solvent was removed under reduced pressure. Flash chromatography (SiO2, 50% Et2O-hexanes) yielded the title compound (226 mg, 58%) as a white solid: 1H NMR (CDCl3, 400 MHz) δ 7.64 (dd, 2H, J=7.2 Hz), 7.58 (dd, 2H, J=8.0 Hz), 7.49 (t, 2H, J=7.6 Hz), 7.38 (t, 1H, J=7.0 Hz), 7.34 (d, 2H, J=8.0 Hz), 4.38-4.34 (m, 1H), 3.71 (s, 3H), 3.35 (s, 1H(—OH)), 2.97-2.82 (m, 2H), 2.61-2.43 (m, 2H); 13C NMR (CDCl3, 75 MHz) δ 172.7, 140.5, 139.1, 136.6, 129.6, 128.5, 126.9, 126.7, 68.7, 51.4, 42.3, 40.3.
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