Ethanolamine → 7-Hydroxy-N-(2-hydroxyethyl)-2-oxo-2H-1-benzopyran-3-carboxamide

Participants

Reaction Conditions

Reaction Steps

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:

Provenance & Evidence