Acetic Anhydride → 1-Acetamido-7-naphthol

Participants

Reaction Steps

To a solution of 8-amino-2-naphthol (149.1 g, 0.937 mol) in methanol (1L) was added acetic anhydride (93 mL, 0.984 mol). The reaction was refluxed for 90 minutes and cooled to room temperature. The solvent was removed and the residue was filtered through a plug of silica with ethyl acetate. The solvent was removed to yield 175.8 g (93%) of the title compound as a dark purple solid. An analytical sample was further purified by reverse phase preparative HPLC to yield a pink solid: mp 161-162° C.; 1H NMR (DMSO-d6): δ 2.15 (3H, s), 7.09 (1H, dd, J=1.95 Hz, J=8.79 Hz), 7.20-7.26 (2H, m), 7.49 (1H, d, J=7.31 Hz), 7.63 (1H, d, J=8.11 Hz), 7.77 (1H, d, J=8.81 Hz), 9.76 (1H, s), 9.79 (1H, s); MS (ESI) m/z202 (M+H)+.

Provenance & Evidence