6-Methoxy-alpha-tetralone → 6-Methoxynaphthalen-1-ol

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Reaction Steps

A mixture of 6-methoxy-1-tetralone (20.84 g, 118.3 mmol), 10% Pd/C (10.1 g), and p-cymene (500 mL) was heated at reflux for 60 hours. The suspension was cooled to room temperature and filtered through Celite. The solid was washed with ethyl acetate until UV clear and the combined organic solution was extracted with 1 N sodium hydroxide (3×200 mL). The combined aqueous layers were made acidic with 6N HCl and extracted with ethyl acetate (3×300 mL). The combined organic layers were dried over magnesium sulfate and filtered. Evaporation of the solvent and purification on a silica column (25% ethyl acetate-hexanes) yielded 17.02 g (83%) of the title compound as a light brown solid. An analytical sample was prepared by purification on a second silica column (40-60% dichloromethane-hexanes) to yield a white solid: mp 73-75° C.; 1H NMR (DMSO-d6): δ 3.85 (3H, s), 6.70-6.74 (1H, m), 7.06 (1H, dd, J=2.34 Hz, J=9.15 Hz), 7.20-7.27 (3H, m), 8.02 (1H, d, J=9.12 Hz), 10.01 (1H, s); MS (ESI) m/z174 (M-H)−.

Provenance & Evidence