Trifluoroacetic acid → N-(4-fluorobenzyl)-N-(3-fluorophenyl)-4-piperidinamine

Participants

Reaction Conditions

Reaction Steps

Tert-butyl 4-[3-fluoro(4-fluorobenzyl)anilino]-1-piperidinecarboxylate 8 (25.5 g) was dissolved in dichloromethane and the solution was cooled to 0° C. TFA (30 ml) was added to the solution and the reaction mixture was stirred at room temperature. After 1 h 30, TFA (20 ml) was added and the reaction mixture was stirred for a further 30 minutes. The solvent was removed under vacuum and the residue was taken up in dichloromethane and water. The aqueous phase was alkalized by addition of NaOH and washed with dichloromethane. The combined organic layers were dried over MgSO4 and concentrated. The crude was purified by chromatography (eluant: CH2Cl2/MeOH/NH4OH 95/5/0.5) to give N-(4-fluorobenzyl)-N-(3-fluorophenyl)-4-piperidinamine (18.4 g) as a free base.

Provenance & Evidence