Glyoxylic Acid → HCID 15236522, compound

Participants

Reaction Steps

Deionized water (10.3 g), 98% 4-acetamidophenol (15.1 g 0.1 mole), 50% aqueous glyoxylic acid (14.8 g, 0.1 mole), and methanol (50.5 g) were added to a beaker and mixed using a magnetic stirrer bar. Unsymmetrical ethylenediaminediacetic acid (19.5 g), prepared by the procedure of Example A, was added and the mix cooled in an ice-water bath. The pH of the mix was adjusted, while stirring, to approximately 8.0 with 50% sodium hydroxide solution. The temperature of the mix was maintained at less than 20° C. during the caustic addition. The ice-water bath was removed and the mix adjusted to pH 8.7 and stirred at 25°-32° C. for approximately 2 hours. The mix was transferred to a round-bottom reaction flask equipped with a water-cooled reflux condenser, magnetic stirrer bar, thermometer, and a heating mantle. The mix was heated, with stirring, at 70° C. for 8 hours and then cooled and filtered using a medium glass frit funnel and vacuum. The solids were allowed to dry by exposure to air for 7 hours and then placed in a vacuum oven and dried at 55°-60° C. for several hours. Approximately 29.6 g of solids were collected. The material was then agitated with approximately 300 g of acetone and filtered using a medium glass frit funnel and house vacuum. The solids were washed once again with an additional 300 g of acetone, air dried and then placed in a vacuum oven for one hour at 55°-60° C. Approximately 26.7 g of 2-[(2-{[bis(carboxymethyl)]-amino}ethyl)amino]-2-(5-acetamido-2-hydroxyphenyl)ethanoic acid, sodium salt were collected. These solids and 180 g of deionized water were placed in a beaker and stirred with a magnetic stirrer bar. The pH was adjusted to 2.2 with concentrated hydrochloric acid at which point the acid form of the product began to precipitate from solution. The product was collected by filtration and washed with approximately 150 g of deionized water. The product, 2-[(2-{[bis(carboxymethyl)]amino}ethyl)amino]-2-(5-acetamido-2-hydroxyphenyl)ethanoic acid was dried in a vacuum oven at 55°-60° C. for several hours. Approximately 14.2 g of product were obtained. Proton NMR verified the structure of the product. (See Table I.)

Provenance & Evidence