Hydrochloric Acid → 1-(9-Methyl-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indol-7-yl)-4-phenethylpiperazin-2-one hydrochloride

Participants

Reaction Steps

tert-Butyl 9-methyl-7-(2-oxo-4-phenethylpiperazin-1-yl)-3,4-dihydro-1H-pyrido[3,4-b]indole-2(9H)-carboxylate (35 mg, 0.071 mmol) was dissolved in MeOH (2 mL), and 2 N HCl in Et2O (10 mL) was added. The reaction was allowed to proceed for 18 h. The mixture was concentrated, and the residue was partitioned between CH2Cl2 and sat. Na2CO3 solution. The organic phase was removed, and the aqueous phase was back extracted with CH2Cl2. The combined organic extracts were dried over Na2SO4, filtered and concentrated to dryness. The residue was dissolved in MeOH (1 mL), treated with 2 N HCl in Et2O (12 μL, 0.024 mmol), and concentrated to provide the title compound (10 mg, 33%) as a white solid: 1H NMR (500 MHz, CD3OD) δ 7.60 (d, J=8.3 Hz, 1H), 7.45 (s, 1H), 7.41-7.34 (m, 4H), 7.33-7.27 (m, 1H), 7.67 (d, J=8.2 Hz, 1H), 4.54 (s, 2H), 4.24-4.15 (m, 2H), 4.15-4.03 (m, 2H), 3.91-3.76 (m, 2H), 3.72 (s, 3H), 3.61-3.54 (m, 4H), 3.22-3.16 (m, 2H), 3.14-3.08 (m, 2H); ESI MS m/z 389 [M+H]+; HPLC (Method B) 94.4% (AUC), tR=10.2 min.

Provenance & Evidence