2-[acetyl(carboxymethyl)amino]acetic acid

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A crude reaction mixture of N-acetyliminodiacetic acid was prepared from acetamide (5.90 g; 0.10 mol)) by the process described in French Pat. No. 2,523,576. This crude product was dissolved in a 20% aqueous hydrochloric acid solution and the resulting mixture was added to a 250 ml 3-necked flask equipped with an addition funnel and thermometer. Phosphorous acid (8.61 g; 0.105 mol) was added and the solution was heated to a temperature of 106° C.-107° C. When this temperature had been reached, formaldehyde (8.23 g of a 44% aqueous solution; 0.212 mole) was added to the mixture in the flask over a period of 30 minutes. After addition of formaldehyde was complete, the temperature was maintained at 106°-107° C. for an additional period of 3.5 hour. The reaction mixture was concentrated under reduced pressure and a precipitate formed. The product was collected by filtration to yield 14.4 g of N-phosphonomethyliminodiacetic acid (63% yield based on the starting amount of acetamide). the resulting mixture was added to a 250 ml 3-necked flask equipped with an addition funnel the solution was heated to a temperature of 106° C.-107° C 0.212 mole) was added to the mixture in the flask over a period of 30 minutes the temperature was maintained at 106°-107° C. for an additional period of 3.5 hour The reaction mixture was concentrated under reduced pressure a precipitate formed The product was collected by filtration

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A crude reaction mixture of N-acetyliminodiacetic acid was prepared from acetamide (5.90 g; 0.10 mol)) by the process described in French Pat. No. 2,523,576. This crude product was dissolved in a 20% aqueous hydrochloric acid solution and the resulting mixture was added to a 250 ml 3-necked flask equipped with an addition funnel and thermometer. Phosphorous acid (8.61 g; 0.105 mol) was added and the solution was heated to a temperature of 106° C.-107° C. When this temperature had been reached, formaldehyde (8.23 g of a 44% aqueous solution; 0.212 mole) was added to the mixture in the flask over a period of 30 minutes. After addition of formaldehyde was complete, the temperature was maintained at 106°-107° C. for an additional period of 3.5 hour. The reaction mixture was concentrated under reduced pressure and a precipitate formed. The product was collected by filtration to yield 14.4 g of N-phosphonomethyliminodiacetic acid (63% yield based on the starting amount of acetamide). the resulting mixture was added to a 250 ml 3-necked flask equipped with an addition funnel the solution was heated to a temperature of 106° C.-107° C 0.212 mole) was added to the mixture in the flask over a period of 30 minutes the temperature was maintained at 106°-107° C. for an additional period of 3.5 hour The reaction mixture was concentrated under reduced pressure a precipitate formed The product was collected by filtration

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:195.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: N-acetyliminodiacetic acid (XVI) monohydrate (45 g) and varying amounts of water and acetic acid were heated at 175° C. or 195° C. for various periods of time. After cooling to room temperature, the mixture was filtered. The solid was washed with water (10 mL) and dried to give 1,4-di(carboxymethyl)-2,5-diketopiperazine. The table below shows the yields of solid under various conditions. After cooling to room temperature the mixture was filtered The solid was washed with water (10 mL) dried