tert-Butyl 4-(3-aminophenyl)-5,6-dihydropyridine-1(2H)-carboxylate → tert-Butyl 4-(3-aminophenyl)piperidine-1-carboxylate

Participants

Reaction Steps

A mixture of tert-butyl 4-(3-aminophenyl)-3,6-dihydro-1 (2H)-pyridinecarboxylate (3.10 g, 11.3 mmol) and 10% Pd/C (1.00 g) in ethanol (100 mL) was hydrogenated at room temperature using the balloon method for 2 days. The reaction mixture was filtered through Celite and washed with ethanol. The combined ethanol extracts were concentrated in vacuo and the residue was chromatographed on silica (dichloromethane: methanol:isopropylamine 95:5:1) to give the desired product (2.63 g, 84%). 1H NMR (400 MHz, CDCl3) δ 7.10 (t, 1H, J=7.6 Hz), 6.62 (d, 1H, J=8.4 Hz), 6.60-6.59 (m, 2H), 4.27-4.18 (m, 2H), 3.62-3.58 (m, 2H), 2.80-2.72 (m, 2H), 2.62-2.59 (m, 1H), 1.89-1.52 (m, 4H), 1.49 (s, 9H); ESMS m/e: 277.2 (M+H)+.

Provenance & Evidence