Acetic Anhydride → 5-Acetamido-phthalide

Participants

Reaction Steps

In tetrahydrofuran (100 ml) was dissolved 5-aminophthalide (10 g, 67.05 mmol), and triethylamine (18.64 ml, 134 mmol) was added thereto. To the resulting mixture was added dropwise acetic anhydride (12.61 ml, 134 mmol) under ice-cooling, followed by stirring at room temperature for 3 hours. After addition of a 5% aqueous solution of sodium hydrogen carbonate, the precipitated white solid was separated by filtration, washed several times with water, and then dried to give 5-acetamidophthalide (12.45 g, 97%).

Provenance & Evidence