GENERAL STEPS: 1-benzyl-4-(ethylamino)piperidine-4-carboxamide (7.39 g, 28.3 mmol) was dissolved in methanol (100 mL) and 20% Pd(OH)2/C (50% water wetted, 1.48 g) was added. The mixture was placed in a Parr shaker and hydrogenated at 50 psi hydrogen pressure overnight at room temperature. Upon completion of the reaction, the mixture was filtered through a Celite pad and the filtrate was concentrated to give the colorless solid product 4-(ethylamino)-4-piperidinecarboxamide (4.84 g, quantitative yield). Product characterization data: APCI MS (M + 1) 172.2; 1H NMR (400 MHz, CD2Cl2) δ 2.89 (ddd, J = 12.9, 8.7, 3.3 Hz, 2H), 2.75 (ddd, J = 12.9, 6.6, 3.7 Hz, 2H), 2.45 (q, J = 7.2 Hz, 2H), 1.95 ( ddd, J = 13.7, 8.3, 3.7 Hz, 2H), 1.55 (ddd, J = 13.7, 6.6, 3.3 Hz, 2H), 1.08 (t, J = 7.2 Hz, 3H).
