Trifluoroacetic acid → HCID 53814908, compound

Participants

Reaction Steps

To a solution of 4-(tert-butyloxycarbonyl)-1-[1-(4-fluorophenyl)-2-methoxyethyl]piperazine (1.46 g, 4.3 mmol) in CH2Cl2 (40 mL) was added trifluoroacetic acid (4 mL), and the mixture stirred at room temperature for 3 h. The solvent was evaporated and the residue azeotroped with toluene (2×20 mL). The residue was partitioned between EtOAc (2×50 mL) and Na2CO3 solution (sat., 50 mL). The combined organic phases were dried (Na2SO4) and evaporated. The residue was chromatographed on silica gel, eluting with CH2Cl2 :MeOH:NH3 (90:10:1), to afford the piperazine (0.95 g, 92%) as a pale yellow oil. 1H NMR (360 MHz, CDCl3) δ2.37-2.55 (4H, m), 2.86-2.89 (4H, m), 3.29 (3H, s), 3.45-3.48 (1H, m), 3.61 (1H, dd, J=9.9 and 5.2 Hz), 3.71 (1H, dd, J=9.9 and 5.8 Hz), 7.00 (2H, dd, JHA-HB =8.7 Hz and JHA-F =8.7 Hz), 7.27 (2H, dd, JHB-HA =8.7 Hz and JHB-F =5.6 Hz). MS (ES+) (239, M+1).

Provenance & Evidence