Hydrochloric Acid → N-[3-(4-Piperidinyl)phenyl]propanamide

Participants

Reaction Steps

Into a stirred solution of tert-butyl 4-[3-(propionylamino)phenyl]-1-piperidinecarboxylate (18.8 g, 0.0543 mmol) in dioxane (100 mL) at 5° C. was bubbled HCl gas for 2 h. The solvent was removed in vacuo, the residue was dissolved in water (100 mL) and neutralized by adding 10% KOH aqueous solution. The aqueous layer was extracted (3×200 mL) with a mixture of CHCl3/isopropyl alcohol (3:1), and the combined organic layers were washed with brine (100 mL), dried over Na2SO4, filtered and concentrated in vacuo. The residue was purified by column chromatography on silica using 5% of NH3 (2.0 M in methanol) in CH2Cl2 to afford the desired product (12.6 g, 99%). 1H NMR (400 MHz, CDCl3) δ 7.44 (s, 1H), 7.32 (d, 1H, J=7.2 Hz), 7.28–7.21 (m, 1H), 7.09 (s, 1H), 6.97 (d, 1H, J=7.6 Hz), 3.18 (d, 2H, J=12.6 Hz), 2.73 (dt, 2H, J=2.2, 11.2 Hz), 2.65–2.57 (m, 1H), 2.38 (q, 2H, J=7.4 Hz), 1.83 (d, 2H, J=12.1 Hz), 1.70–1.61 (m, 3H), 1.25 (t, 3H, J=7.5 Hz); ESMS m/e: 233.1 (M+H)+.

Provenance & Evidence