Potassium Carbonate → 4-Acetyl-1-(3-aminopropyl)-4-phenylpiperidine

Participants

Reaction Steps

A solution of 4-Acetyl-4-phenylpiperidine (7, 1.53 g, 7.50 mmol), 3-bromo-propylamine hydrobromide (1.64 g, 7.50 mmol) and potassium carbonate (1.24 g, 9.00 mmol) was stirred in refluxing 1,4-dioxane (50 mL) for 12 h. After removal of dioxane, water (50 mL) was added and the pH was adjusted to 11-12 by addition of 1 N aqueous NaOH. The mixture was extracted with CH2Cl2 (100 mL+3×50 mL). The combined organic solutions were dried over magnesium sulfate and concentrated. The residue was purified by flash chromatography (EtOAc-MeOH-Et3N 100/40/20), giving the desired product as a colorless oil (780 mg, 40%): 1H NMR δ 1.56 (p, J=7 Hz, 2 H), 1.84 (s, 3 H), 1.98 (m, 2 H), 2.15 (br t, J=12 Hz, 2 H), 2.29 (t, J=7 Hz, 2 H), 2.41 (br d, J=12 Hz, 2 H), 2.66 (t, J=7 Hz, 4 H), 7.18-7.30 (m, 5 H); 13C NMR δ 26.28, 31.11, 33.43, 41.47, 51.62, 55.31, 57.19, 77.32, 77.74, 78.17, 126.95, 127.69, 129.44, 142.25, 210.15.

Provenance & Evidence