Reaction Steps
To a solution of tert-butyl 8,9-dichloro-1,4,5,6-tetrahydroazepino[4,5-b]indole-3(2H)-carboxylate (0.40 g, 1.1 mmol) in DMF (5 mL), sodium hydride (60% dispersion in mineral oil, 68 mg, 1.7 mmol) was added. After 25 min, 4-fluorophenoxy ethyl bromide (0.34 mL, 2.3 mmol) was added. The reaction was quenched with saturated aqueous NH4Cl after 2 h and extracted with EtOAc (3×15 mL). The combined organic extracts were washed with brine, dried over Na2SO4, decanted, and concentrated. The crude product was purified by column chromatography (Biotage, 40M) with heptane/EtOAc (gradient, 9:1 to 17:3) to give 0.43 g (78%) of a white foam: 1H NMR (300 MHz, CDCl3) δ 7.51 (d, J=3.8 Hz, 1H), 7.40 (d, J=6.0 Hz, 1H), 6.92 (t, J=8.7 Hz, 2H), 6.70 (m, 2H), 4.40 (t, J=5.3 Hz, 2H), 4.13 (t, J=5.3 Hz, 4H), 3.69 (m, 4H), 3.08 (m, 2H), 2.90 (m, 2H), 1.48 (s, 9H); IR (diffuse reflectance) 1687, 1505, 1468, 1414, 1366, 1296, 1268, 1248, 1218, 1169, 1114, 1105, 865, 827, 746 cm−1; MS (ES+) m/z 493 (M+H+), 516, 515, 366, 364, 265, 253, 138, 94, 91, 85; Anal. Calcd for C25H27Cl2FN2O3: C, 60.86; H, 5.51; N, 5.68, found: C, 60.91; H, 5.61; N, 5.64.