Sodium Hydroxide → 2H-benzazepine

Participants

Reaction Steps

To a solution of the N-acetyl benzazepine (0.14 g, 0.40 mmol) from step I above in methanol (10 mL) was added an aqueous 2N solution of sodium hydroxide (10 mL). The reaction solution was heated under reflux for 72 hours and then cooled to room temperature. The resultant reaction mixture was extracted with dichloromethane, washed with water and aqueous saturated sodium bicarbonate, dried over sodium sulfate and concentrated in vacuo. The residue obtained was purified by flash column chromatography (dichloromethane to 90:9:1 dichloromethane/methanol/concentrated ammonium hydroxide) to give the desired 2H-benzazepine (0.11 g, 89%) as a white foam: 1H NMR (DMSO-d6, 500 MHz) δ 7.35 (t, J=7.5 Hz, 2H), 7.24 (t, J=7.5 Hz, 1H), 7.14 (d, J=7.5 Hz, 2H), 6.84 (d, J=2.5 Hz, 1H), 6.65-6.60 (m, 1H), 6.49-6.38 (br, 1H), 4.33 (d, J=8.5 Hz, 1H), 3.95 (d, J=14.5 Hz, 1H), 3.77 (d, J=14.5 Hz, 1H), 3.71 (t, J=5.0 Hz, 4H), 3.10-2.87 (m, 6H), 2.21-2.12 (m, 1H), 2.03-1.85 (m, 1H).

Provenance & Evidence