反应详情

Trifluoroacetic acid (90 mL) was added to a stirred, cooled (0° C.) solution of 1,1-dimethylethyl 4-[2-methoxy-4-(trifluoromethoxy)phenyl]-1-piperazinecarboxylate (Description 17, 3.4 g) in dichloromethane (135 mL) and the mixture was stirred at room temperature for 1 h. The mixture was allowed to warm to room temperature, saturated aqueous sodium bicarbonate solution (380 mL) was added and the mixture was extracted with dichloromethane. The combined organic fractions were dried (MgSO4) and the solvent was evaporated under reduced pressure to give the title compound as a pale brown solid (1.84 g, 74%). 1H NMR (250 MHz, CDCl3) δ3.28-3.58 (8H, m), 3.87 (3H, s), 6.77 (1H, d, J 1.9 Hz), 6.84 (1H, d, J 8.9 Hz), and 6.91-6.95 (1H, m).

1. temperatureto warm to room temperature
2. extractionthe mixture was extracted with dichloromethane
3. dry with materialThe combined organic fractions were dried (MgSO4)
4. customthe solvent was evaporated under reduced pressure