Reaction Steps
In a dried, 25 mL round bottom flask under argon, indole-3-carboxaldehyde (300 mg, 2.07 mmol) was dissolved in anhydrous methanol (8 mL). Acetophenone (240 μL, 2.07 mmol) and piperidine (100 μL, 1.00 mmol) was added. The reaction was stirred under reflux for 18 hours. 10% Acetic acid was added (10 mL), precipitating 248 mg of a crude yellow solid. This was recrystallized in 100% EtOH, filtered, and dried under vacuum, yielding a pure, yellow solid (198 mg, 39%, 247.29 MW). 1H NMR (600 MHz, d6-DMSO): δ 8.133-8.114 (m, 3H, phenyl-2,6H, indole-2H), 8.095-8.081 (m, 1H, indole-4H), 8.075-8.049 (d, J=15.6, 1H, C═CH), 7.668-7.642 (d, J=15.6, 1H, C═CH), 7.655-7.629 (m, 1H, phenyl-4H), 7.581-7.556 (t, J=1.5, 2H, phenyl-3,5H), 7.504-7.490 (m, 1H, indole-7H), 7.254-7.231 (m, 2H, indole-5,6H). 13C NMR (150 MHz, d6-DMSO): δ 188.8, 139.1, 138.5, 137.5, 133.4, 132.4, 128.7, 128.2, 125.1, 122.8, 121.2, 120.4, 115.3, 112.8, 112.5. Melting point: 167-170° C. TLC (in 2:1 ethyl acetate:hexanes) Rf=0.48. Elemental analysis calculated for C17H13NO: C, 82.57; H, 5.30; N, 5.66. found: C, 82.19; H, 5.35; N, 5.63.
