Stannous Chloride → 3-prop-2-ynyl-2,3,4,5-tetrahydro-1H-benzo[d]azepin-7-ylamine

Participants

Reaction Steps

7-Nitro-3-prop-2-ynyl-2,3,4,5-tetrahydro-1H-benzo[d]azepine (589 mg, 2.56 mmol) was dissolved in ethyl acetate (80 mL) and ethanol (30 mL). Tin (II) chloride dehydrate (2.88 g, 12.80 mmol, 5.0 eq) was added and the reaction was heated at reflux for 18 hours. The reaction was allowed to cool to room temperature and was then concentrated under reduced pressure. The residue was taken up in EtOAc (100 mL) and washed with 10% aqueous KF (70 mL). The organic layer was dried (sodium sulfate), filtered, and concentrated under reduced pressure to obtain 3-prop-2-ynyl-2,3,4,5-tetrahydro-1H-benzo[d]azepin-7-ylamine as a yellow solid (487 mg, 95%). An analytical sample was purified by prep-HPLC using a gradient of 0-30% acetonitrile/water. LCMS (m/e) 201 (M+1); 1H-NMR (CDCl3, 400 MHz) δ 6.91 (d, 1H, J=7.7 Hz), 6.52-6.46 (m, 2H), 3.43 (d, 2H, J=2.3 Hz), 2.91-2.82 (m, 4H), 2.78-2.64 (m, 4H), 2.24-2.19 (m, 1H).

Provenance & Evidence