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To a cold, stirred solution of 3.05 grams (g) [0.05 mole (mol)] of 2-aminoethanol in 30 milliliters (ml) of dioxane was added a suspension of 2.2 g (0.01 mol) of 7-hydroxycoumarin-3-carbonyl chloride [Sherman et al, Anal. Chem. 40:803(1968)] in 75 ml of dioxane. The mixture was stirred at 0° C. for 30 minutes, during which time a thick oil precipitated that solidified upon scratching with a spatula. The dioxane was decanted and the precipitate dissolved in water. Adjustment of the pH of the aqueous solution to 7.0 with glacial acetic acid resulted in precipitation of a tan solid. The solid precipitate was recrystallized from water to give 1.3 g (52% yield) of N-(2-hydroxyethyl)-7-hydroxycoumarin-3-carboxamide as a white solid with a melting point of 244°-245° C. Elemental analysis and infrared spectral data for the product are given below:

1. additionwas added
2. customprecipitated that solidified
3. customThe dioxane was decanted
4. dissolutionthe precipitate dissolved in water
5. customAdjustment of the pH of the aqueous solution to 7.0 with glacial acetic acid resulted in precipitation of a tan solid
6. customThe solid precipitate was recrystallized from water