Acetic Anhydride → WS-5995 A

Participants

Reaction Steps

The entire amount of the 2-(3,5-dihydroxy-1,4-naphthoquinon-2-yl)-3-methoxy-5-methylbenzoic acid obtained above was dissolved in ethyl acetate (10 ml) and while the solution was stirred at room temperature, a mixture (1 ml:10 ml) of trifluoroacetic anhydride and acetic anhydride was added. The mixture was further stirred at the same temperature for an hour. This reaction mixture was washed with water and dilute aqueous sodium carbonate in that order, followed by drying over magnesium sulfate. The solvent was then distilled off and the residual brown oil was subjected to silica gel column chromatography to give vermillion-colored crystals (20 mg).

Provenance & Evidence