7-Amino-4-carboxymethylcoumarin, also known as 7-aminocoumarin-4-acetic acid, can be used as a chemical and pharmaceutical intermediate.
To a 2L round-bottomed flask equipped with a condenser was added 7-N-(ethoxycarbonyl)aminocoumarin-4-acetic acid (101 g, 0.345 mol), NaOH (138 g, 3.45 mol) and H2O (900 mL). The reaction mixture was stirred at reflux for 16 hours. After cooling to room temperature, the pH of the reaction mixture was adjusted to 2 by dropwise addition of H2SO4. The resulting yellow precipitate formed was collected by filtration to give 64.3 g (85%) 5 as a fluffy yellow powder. The product was sufficiently pure by NMR analysis. Yield 64.3 g, 85%.
