Trifluoroacetic acid → 4-Pentafluoroethyloxy-piperidine

Participants

Reaction Steps

Trifluoroacetic acid (1.15 mL) was added dropwise to a solution of tert-butyl 4-(2,2,2-trifluoroethoxy)piperidine-1-carboxylate (prepared in an analogous manner to Intermediate 203, 1.14 g, 4.0 mmol) in DCM (10 mL) at room temperature. The reaction mixture was stirred at room temperature for 16 h. The mixture was then concentrated under vacuum, the crude residue was dissolved in water and product was extracted with diethylether (2 times). The aqueous phase was basicified to pH 10 using solid potassium carbonate and extracted with DCM (4 times). The organic extracts were combined, dried over sodium sulfate and concentrated under vacuum to afford the title compound (610 mg, 83%). 1H NMR (300 MHz, CDCl3) δ ppm 3.84 (2H, q), 3.53 (1H, m), 3.10 (2H, m), 2.61 (2H, m), 1.76 (2H, m) and 1.54 (2H, s).

Provenance & Evidence