Trifluoroacetic acid → 1-[1-(4-Methoxy-2,3-dimethyl-phenyl)-ethyl]-piperazine
Reaktionsgleichung
C(OC([N:8]1[CH2:13][CH2:12][N:11]([CH:14]([C:16]2[CH:21]=[CH:20][C:19]([O:22][CH3:23])=[C:18]([CH3:24])[C:17]=2[CH3:25])[CH3:15])[CH2:10][CH2:9]1)=O)(C)(C)C.FC(F)(F)C(O)=O>ClCCl>[CH3:23][O:22][C:19]1[CH:20]=[CH:21][C:16]([CH:14]([N:11]2[CH2:10][CH2:9][NH:8][CH2:13][CH2:12]2)[CH3:15])=[C:17]([CH3:25])[C:18]=1[CH3:24]Komponenten
4
Versuchsvorschrift
To an ice chilled solution containing 4-[1-(4-methoxy-2,3-dimethyl-phenyl)-ethyl]-piperazine-1-carboxylic acid tert-butyl ester (0.4 g 1.38 mmol) and 10 ml dichloromethane, was added trifluoroacetic acid (2 ml) dropwise. The reaction was stirred at room temperature for 2 hours. The reaction was concentrated. The residue was purified by flash chromatography on silica gel eluted with 10% MeOH(NH3)/dichloromethane. 1-[1-(4-Methoxy-2,3-dimethyl-phenyl)-ethyl]-piperazine was obtained as a yellow oil (0.16 g 47%). Analysis H1 NMR (400 MHz, CDCl3): 7.23 (1H, d), 6.69 (1H, d), 3.8 (3H, s), 3.55 (1H, q), 3.484 (2H, s), 2.838 (4H, m), 2.47 (2H, m), 2.38 (2H, m), 2.271 (3H, s), 2.167 (3H, s), 1.26 (3H, d). MS (LC-MS): Calculated for C15H24N2O 248.36, found 249.25 (M+).