Hydrochloric Acid → (4-(5-Fluoro-2-(trifluoromethyl)phenyl)piperidin-1-yl)(4,5,6,7-tetrahydro-1H-pyrazolo[4,3-c]pyridin-3-yl)methanone Hydrochloride

Participants

Reaction Steps

To a solution of tert-butyl 3-(4-(5-fluoro-2-(trifluoromethyl)phenyl)piperidine-1-carbonyl)-6,7-dihydro-1H-pyrazolo[4,3-c]pyridine-5(4H)-carboxylate (45, 120 mg, 0.24 mmol) in CH2Cl2 (2 mL) was added HCl (2N in Et2O, 2 mL). The mixture stirred for 18 h at ambient temperature. Additional HCl (2N in Et2O, 1 mL) was added and the mixture was stirred at ambient temperature for 3 h. The reaction mixture was diluted with Et2O (20 mL) and the resulting solids were collected by filtration to provide (4-(5-fluoro-2-(trifluoromethyl)phenyl)piperidin-1-yl)(4,5,6,7-tetrahydro-1H-pyrazolo[4,3-c]pyridin-3-yl)methanone hydrochloride (46) as a white solid (104 mg, 99%): 1H NMR (300 MHz, DMSO-d6) δ 9.54-9.19 (m, 2H), 7.84 (dd, J=9.0, 5.7 Hz, 1H), 7.60-7.51 (m, 1H), 7.32-7.20 (m, 1H), 5.32-5.12 (m, 1H), 4.78-4.60 (m, 1H), 4.29-4.16 (m, 2H), 3.43-3.30 (m, 2H, overlaps with H2O), 3.26-3.06 (m, 2H), 2.95 (t, J=5.4 Hz, 2H), 2.89-2.72 (m, 1H), 1.84-1.65 (m, 4H) missing N—H pyrazole; ESI MS m/z 397 [M+H]+.

Provenance & Evidence