Hydrochloric Acid → 2-Amino-1-(4-methoxyphenyl)propan-1-one--hydrogen chloride (1/1)

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Reaction Steps

4′-Methoxy-2-bromopropiophenone (10 g, 41 mmol.) was dissolved in a mixture of THF (100 mL) and water (20 mL), followed by addition of sodium azide (6.5 g, 0.1 mole). The slurry was vigorously stirred for 5 hours and TLC indicated a completed conversion to 4′-methoxy-2-azidopropiophenone. The aqueous layer was then removed and the organic layer was further diluted with ethanol (200 mL). Concentrated hydrochloride (5 mL, about 60 mmol.) and palladium on carbon (10%, 2 g) were added and hydrogenation was performed using Parr apparatus at 20 psi for 1 hour. The product precipitated during the hydrogenation was re-dissolved by addition of methanol (100 mL). After filtration to remove the catalyst, the solution was concentrated to form a solid. It was stirred with ether (300 mL) and solids were filtered and dried under vacuum at 50° C. overnight to give the titled compound (8.8 g, 100%) MS: 180 (MH+), 162 (M-NH3). Proton NMR (DMSO-d6) δ: 7.96(2H, brs), 7.79(2H, d, J=8.4 Hz), 6.87(2H, d, J=8.4 Hz), 4.49(1H,brs), 1.17(2H, d, J=6.9 Hz).

Provenance & Evidence