1-[(3-Methoxyphenyl)methyl]piperidin-4-one → 4-(3-Chloro-4-fluorophenyl)-1-(3-methoxybenzyl)piperidin-4-ol

Participants

Reaction Steps

To (3-chloro-4-fluorophenyl)magnesium bromide (6.8 ml of a 0.5 M solution in tetrahydrofuran, 3.4 mmol) was added a solution of 1-(3-methoxybenzyl)piperidin-4-one (500 mg, 2.28 mmol) from Step B of Example 12 in tetrahydrofuran (10 mL). The reaction mixture was stirred at ambient temperature for 3 h and then was quenched with saturated ammonium chloride. The mixture was extracted with ethyl acetate (2×) and the combined organics were washed with brine, dried over sodium sulfate and concentrated in vacuo. Purification by silica gel chromatography (10% ethyl acetate/methylene chloride to ethyl acetate) gave 4-(3-chloro-4-fluorophenyl)-1-(3-methoxybenzyl)piperidin-4-ol (209 mg, 26%): 1H NMR (CDCl3, 500 MHz) δ 7.59-7.55 (m, 1H), 7.39-7.33 (m, 1H), 7.27-7.22 (m, 1H), 7.13-7.07 (m, 1H), 6.95-6.93 (m, 2H), 6.83-6.80 (m, 1H), 3.84 (s, 3H), 3.60-3.55 (m, 2H), 2.82-2.73 (m, 2H), 2.48-2.40 (m, 2H), 2.18-2.02 (m, 2H), 1.72-1.68 (m, 2H), 1.59-1.56 (m, 1H).

Provenance & Evidence