4-Piperidinecarboxylic acid → 1-Acetylpiperidine-4-carboxylic acid

Participants

Reaction Steps

Isonipecotic acid (25.0 g, 0.19 mol) was dissolved in acetic anhydride (100 mL) and the solution stirred at reflux for 8 h, then the solvent was removed under reduced pressure and the crude compound crystallized from MeOH/ether to afford the title compound as a white solid (24.4 g, 74%). m.p. 171° C. 1H NMR (DMSO): 1.2-1.5 (m, 2H), 1.65-1.85 (m, 2H), 1.942 (s, 3H), 2.35-2.5 (m, 1H), 2.641 (t, J=11.7 Hz, 1H), 3.038 (t, J=11.7 Hz, 1H), 3.69 (d, J=13.5 Hz, 1H), 4.15 (d, J=13.2 Hz, 1H), 12.22 (bs, 1H). IR (KBr): 1721, 1613, 1316, 1202 (cm−1). MS (m/z): 171, 128, 82.

Provenance & Evidence