Acetic Acid → 4-(2-Chloro-5-fluorophenyl)piperidine Hydrochloride

A mixture of 4-(5-fluoro-2-(trifluoromethyl)phenyl)-1,2,3,6-tetrahydropyridine hydrochloride (16, 0.310 g, 1.31 mmol) PtO2 (0.085 g, 0.37 mmol), and HOAc (71 μL, 1.31 mmol) in EtOAc (12 mL) stirred at ambient temperature for 18 under an atmosphere of H2 (1 atm). The reaction mixture was diluted with EtOAc (50 mL) and CH3OH (5 mL) and filtered over Celite and the filtrate was concentrated under reduced pressure and dissolved in CH2Cl2 (5 mL). To this solution was added HCl (2.0 N solution in Et2O, 2.0 mL) and the mixture stirred at ambient temperature for 5 min. The resulting suspension was diluted with Et2O (20 mL) and the solids collected by filtration to give 4-(2-chloro-5 fluorophenyl)piperidine hydrochloride (17) as an off-white solid (215 mg, 48%): 1H NMR (300 MHz, DMSO-d6) δ 8.93-8.20 (m, 2H), 7.58-7.48 (m, 1H), 7.22-7.12 (m, 1H), 7.11-7.01 (m, 1H), 3.43-3.30 (m, 2H), 3.29-3.16 (m, 1H), 3.14-2.89 (m, 2H), 2.01-1.68 (m, 4H); ESI MS m/z 214 [M+H]+.

1. filtrationfiltered over Celite
2. concentrationthe filtrate was concentrated under reduced pressure
3. dissolutiondissolved in CH2Cl2 (5 mL)
4. additionTo this solution was added HCl (2.0 N solution in Et2O, 2.0 mL)
5. stirringthe mixture stirred at ambient temperature for 5 min
6. additionThe resulting suspension was diluted with Et2O (20 mL)
7. filtrationthe solids collected by filtration

ORD record

ord-79cbfc3192ed44ca9dd32960564bd7f5

Source dataset

uspto-grants-2016_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09434727B2