Water → (+)-1-(6-Methoxy-2-naphthyl)-2-amino-1-propanone dimethyl acetal

Reaction equation

[CH3:1][O:2][C:3]([O:24][CH3:25])([C:12]1[CH:21]=[CH:20][C:19]2[C:14](=[CH:15][CH:16]=[C:17]([O:22][CH3:23])[CH:18]=2)[CH:13]=1)[CH:4]([NH:6]C(OCC)=O)[CH3:5].[OH-].[K+].O>CO>[CH3:1][O:2][C:3]([O:24][CH3:25])([C:12]1[CH:21]=[CH:20][C:19]2[C:14](=[CH:15][CH:16]=[C:17]([O:22][CH3:23])[CH:18]=2)[CH:13]=1)[CH:4]([NH2:6])[CH3:5]

Participants

Procedure

653 mg (1.8 mmols) of (-)-1-(6-methoxy-2-naphthyl)-2-(ethoxycarbonyl)amino-1-propanone dimethyl acetal and 5 ml of a 30% aqueous potassium hydroxide solution were heated at reflux in 50 ml of methanol for 5 days. After adding 20 ml of water, the mixture was extracted with ethyl acetate (20 ml×3), and the extract was dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was purified by column chromatography (Florisil, ethyl acetate) to obtain 300 mg of (+)-1-(6-methoxy-2-naphthyl)-2-amino-1-propanone dimethyl acetal as colorless crystals having a melting point of 84°-86° C. Yield, 58%.