反应详情

To a stirred solution of ethyl 4-[4-(tert-butyloxycarbonyl)-1-piperazinyl]benzoate (240 mg, 0.718 mmol) in CH2Cl2 (5 mL) was added TFA (5 mL), and the resulting mixture was stirred for 3 hr. The mixture was concentrated in vacuo and the residue was made basic by the addition of sat. NaHCO3, followed by extraction with CHCl3 (2×100 mL). The combined extracts were dried over Na2CO3 and evaporated to give 168 mg ethyl 4-(1-piperazinyl)benzoate (100%) as a yellow oil. 1H-NMR (CDCl3) δ 1.37 (3 H, t, J=7.3 Hz), 3.03 (4 H, t, J=4.9 Hz), 3.29 (4 H, t, J=4.9 Hz), 4.33 (2 H, q, J=7.3 Hz), 6.87 (2 H, dt, J=8.8, 2.4 Hz), 7.91–7.94 (2 H, m).

1. concentrationThe mixture was concentrated in vacuo
2. additionthe residue was made basic by the addition of sat. NaHCO3
3. extractionfollowed by extraction with CHCl3 (2×100 mL)
4. dry with materialThe combined extracts were dried over Na2CO3
5. customevaporated