反应详情

A mixture of tert-butyl 4-(3,4-difluoro-2-(trifluoromethyl)phenyl)-5,6-dihydropyridine-1(2H)-carboxylate (7, 59.0 g, 162.3 mmol) and 10% Pd/C (5.0 g) in EtOH (200 mL) was placed under an atmosphere of H2 (30 psi) at ambient temperature for 72 h. the mixture was filtered through a Celite, and the filtrate was concentrated under reduced pressure to give tert-butyl 4-(3,4-difluoro-2-(trifluoromethyl)phenyl)piperidine-1-carboxylate (8) as a white solid (57.9 g, 97%): 1H NMR (300 MHz, CDCl3) δ7.36-7.28 (m, 1H), 7.12 (m, 1H), 4.24 (br, 2H), 3.06 (m, 1H), 2.80 (m, 2H), 1.78-1.52 (m, 4H), 1.48 (s, 9H); MS (ESI+) m/z 310 [M+H−C4H8]+.

1. filtrationthe mixture was filtered through a Celite
2. concentrationthe filtrate was concentrated under reduced pressure