Hydrazine hydrate (1:1) → 7-Amino-1-(2-methoxyethyl)-1,3,4,5-tetrahydrobenzo[b]azepin-2-one

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Reaction Steps

To a solution of the above 1-(2-methoxy-ethyl)-7-nitro-1,3,4,5-tetrahydro-benzo[b]azepin-2-one in EtOH (10 mL) was sequentially added 10% Pd/C (120 mg) and hydrazine-monohydrate (1 mL). The solution was warmed to reflux for 2.5 h, cooled, filtered through celite, and repeatedly evaporated from toluene to remove residual hydrazine. The residue was recrystallized from EtOAc/heptane to afford transparent prisms of 7-amino-1-(2-methoxy-ethyl)-1,3,4,5-tetrahydro-benzo[b]azepin-2-one (345 mg, 54%) that had the following properties: mp: 134-135° C.; LC/MS (ESI+): 235 (M+H); 1H-NMR (CDCl3, 400 MHz): δ 7.08 (d, J=8.4, 1H), 6.60 (d, J=8.4, 1H), 6.51 (s, 1H), 4.20 (br s, 1H), 3.65 (m, 2H), 3.53 (m, 2H), 3.28 (s, 3H), 2.60 (br s, 1H), 2.27 (m, 2H), 1.58 (m, 3H).

Provenance & Evidence