Acetaldehyde → 4-(Benzyloxy)-1-(2-ethyl-6-methyl-1,2,3,4,5,6-hexahydroazepino[4,3-b]indol-8-yl)pyridin-2(1H)-one

Participants

Reaction Steps

Acetaldehyde (50 μL, 0.88 mmol) and picoline borane complex (47 mg, 0.43 mmol) were added to a suspension of 4-(benzyloxy)-1-(6-methyl-1,2,3,4,5,6-hexahydroazepino[4,3-b]indol-8-yl)pyridin-2(1H)-one hydrochloride (64 mg, 0.18 mmol) in 10:1 CH2Cl2/AcOH (5.0 mL), and the resulting solution was stirred at ambient temperature for 2 h. Additional acetaldehyde (50 μL, 0.88 mmol) was added to the solution, and the resulting mixture was stirred for 18 h. The mixture was neutralized with saturated NaHCO3 solution and extracted with CH2Cl2 (3×20 mL). The combined organic extracts were dried over Na2SO4, filtered and concentrated to dryness. Flash chromatography (12 g ISCO CH2Cl2/(80:18:2 CH2Cl2/MeOH/NH4OH), 100:0 for 2 column volumes to 0:100 over 20 column volumes) provided the title compound (34 mg, 54%) as a yellow solid. 1H NMR (500 MHz, DMSO-d6) δ 7.56 (d, J=7.5 Hz, 1H), 7.48-7.41 (m, 5H), 7.39-7.37 (m, 1H), 7.35 (d, J=2.0 Hz, 1H), 6.87 (dd, J=8.5, 2.0 Hz, 1H), 6.07 (dd, J=7.5, 3.0 Hz, 1H), 5.96 (d, J=3.0 Hz, 1H), 5.14 (s, 2H), 3.88 (s, 2H), 3.66 (s, 3H), 3.03-3.01 (m, 2H), 2.94 (t, J=5.5 Hz, 2H), 2.46-2.42 (m, 2H), 1.78-1.76 (m, 2H), 1.01 (t, J=7.0 Hz, 3H); ESI MS m/z 428 [M+H]+.

Provenance & Evidence