1-(2-Methoxyphenyl)piperazine → Ethyl 4-[4-(2-methoxyphenyl)piperazin-1-yl]butanoate

Participants

Reaction Steps

A stirred mixture of 1-(2-methoxyphenyl)piperazine (1.50 g, 7.8 mmol), ethyl 4-bromobutanoate (0.9 mL, 6.3 mmol), and K2CO3 (0.87 g, 6.3 mmol) in acetonitrile was refluxed overnight. After the mixture was cooled, the mixture was evaporated to dryness and H2O (20 mL) was added to the residue. The aqueous phase was extracted with CH2Cl2 (230 mL). The collected organic layers were dried over Na2SO4 and evaporated under reduced pressure. The crude residue was chromatographed (CHCl3/AcOEt, 1:1, as eluent) to afford pure 13 as a pale yellow oil (1.32 g, 68% yield). 1H NMR: δ 1.24 (t, 3H, J=7.1 Hz, CH2CH3), 1.79-1.89 (m, 2H, CH2CH2CO), 2.34 (t, 2H, J=7.3 Hz, COCH2), 2.41 [t, 2H, J=7.4 Hz, (CH2)2NCH2], 2.63 [br s, 4H, (CH2)2NCH2], 3.06 [br s, 4H, ArN(CH2)2], 3.83 (s, 3H, OCH3), 4.11 (q, 2H, J=7.1 Hz, CH2CH3), 6.82-7.00 (m, 3H, aromatic). GC-MS m/z 307 (M++1, 18), 306 (M+, 77), 261 (32), 205 (100), 190 (37).

Provenance & Evidence