Reaction Steps
Heat CeCl3-7H2O (97 mg, 0.26 mmol) under vacuum at 70° C. for two hours and then warm slowly to 120° C. and continue heating overnight. Cool to room temperature and add THF (3 mL) followed by cyclopentanone 23 (100 mg, 0.26 mmol) and stir the solution for 45 minutes. Cool the reaction to −10° C., add EtMgCl (3.0 M in THF, 87 ul, 0.26 mmol) and stir the reaction for 30 minutes. Quench the reaction with saturated aqueous NH4Cl and extract with EtOAc (2×). Combine the organic extracts, wash with brine, dry (Na2SO4), filter and concentrate. Purify by flash chromatography (10 g silica gel, 40 mL/min, dry loading on 700 mg of silica gel, 0-30% EtOAc/hexanes for 20 minutes and 30% EtOAc/hexanes for 13 minutes) to afford Alcohol 31 (86 mg, 0.207 mmol, 81%). 1H NMR (δ, 400 MHz, CDCl3) 7.36 (d, 2H, J=8.8 Hz), 7.05 (d, 2H, J=8.8 Hz), 6.90-6.87 (m, 2H), 6.83 (dd, 1H, J=8.8, 2.6 Hz), 5.19 (s, 2H), 5.14 (d, 1H, J=6.8 Hz), 5.10 (d, 1H, J=6.8 Hz), 5.05 (d, 1H, J=2.2 Hz), 3.54 (dd, 1H, J=7.6, 7.6 Hz), 3.51 (s, 3H), 3.49 (s, 3H), 2.70 (ddd, 1H, J=2.2, 7.6, 9.6 Hz), 2.22 (dd, 1H, J=13.6, 7.9 Hz), 2.03 (d, 1H, J=13.6 Hz), 1.84 (dd, 1H, J=14.1, 10.1 Hz), 1.67 (dd, 1H, J=14.1, 9.2 Hz), 1.52 (m, 2H), 0.89 (t, 3H, J=7.3 Hz).
