Hydrochloric Acid → Hydrochloric Acid

Participants

Reaction Steps

A solution of HCl in acetic acid (1 M, 30 mL) was added under nitrogen to a mixture of 4-bromophenylhydrazine hydrochloride (4.33 g, 19.37 mmol; Aldrich) and 1-azabicyclo[3.2.2]nonan-4-one (2.70 g, 19.37 mmol; Example 2A). The mixture was stirred at room temperature for 16 hours, then heated at 75° C. for 3 hours. The mixture was cooled to room temperature and concentrated under vacuum to remove most of the acetic acid. Anhydrous ethanol (100 mL) was added to the residue, and the mixture was heated at reflux for 10 minutes, then cooled to room temperature. The precipitate was collected by filtration, washed with ethanol (25 mL) and dried under vacuum to provide the title compound as its HCl salt (3.02 g). A portion of this salt (400 mg) was partitioned between 20% NaOH (25 mL) and chloroform (50 mL) and the organic phase was dried (sodium sulfate) and concentrated. The residue was crystallized from ethyl acetate-ethanol (5:1) to provide the free base of title compound: 1H NMR (300 MHz, methanol-d4) δ 2.14-2.36 (m, 4H), 3.17-3.25 (m, 1H), 3.33-3.45 (m, 2H), 3.45-3.65 (m, 2H), 4.54 (s, 2H), 7.18 (dd, J=8.8, 1.8 Hz, 1H), 7.24 (d, J=9.1 Hz, 1H), 7.51 ppm (d, J=2.4 Hz, 1H); MS(DCI) m/z 291/293 (M+H)+.

Provenance & Evidence