N-(2-hydroxyethyl)-3-oxobutanamide

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

Procedure: To a solution of diketene (42.1 g, 0.5 mol) in dichloromethane (100 ml), ethanolamine (30.5 g, 0.5 mol) was added dropwise at 10°-20.C with stirring, and the reaction was carried out at room temperature for 2 hrs. After pouring H2O (200 ml) into the reaction solution, an aqueous layer was separated, washed thrice with dichloromethane and was obtained N-(2-hydroxyethyl)-3-oxobutanamide as an aqueous solution. an aqueous layer was separated washed thrice with dichloromethane

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 23 ml (0.38 mmol) of ethanolamine were added dropwise to a solution of 30 g of diketene (0.36 mol) in 300 ml tetrahydrofuran at −5 to 0° C. After 1 h stirring at 0° C. no more starting material was detected by thin layer chromatography. The reaction mixture was evaporated and the residue purified by column chromatography. This gave 41.44 g (0.29 mol, 80% yield) as a white solid. The reaction mixture was evaporated the residue purified by column chromatography

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

Procedure: To a solution of diketene (42.1 g, 0.5 mol) in dichloromethane (100 ml), ethanolamine (30.5 g, 0.5 mol) was added dropwise at 10°-20.C with stirring, and the reaction was carried out at room temperature for 2 hrs. After pouring H2O (200 ml) into the reaction solution, an aqueous layer was separated, washed thrice with dichloromethane and was obtained N-(2-hydroxyethyl)-3-oxobutanamide as an aqueous solution. an aqueous layer was separated washed thrice with dichloromethane

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

Procedure: To a solution of diketene (42.1 g, 0.5 mol) in dichloromethane (100 ml), ethanolamine (30.5 g, 0.5 mol) was added dropwise at 10°-20.C with stirring, and the reaction was carried out at room temperature for 2 hrs. After pouring H2O (200 ml) into the reaction solution, an aqueous layer was separated, washed thrice with dichloromethane and was obtained N-(2-hydroxyethyl)-3-oxobutanamide as an aqueous solution. an aqueous layer was separated washed thrice with dichloromethane

Conditions: temp:-2.51; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Acetonitrile (825 g) and diketene (55.0 g) were introduced into a 5,000 mL four-necked flask, and the mixture was cooled so that the temperature in the flask was lowered to −5 to 0° C. Diketene and 2-aminoethanol were simultaneously added dropwise for 4 hours at a rate of 261.5 g/h and 190 g/h, respectively. In such a case, about 2 hours after the commencement of dropwise addition, the reaction system became uneven, causing stirring difficulty. Therefore, cooled acetonitrile (1,000 g) was further added thereto, and dropwise addition was continued under a suspended state. During the addition, cooling was conducted to maintain the temperature in the flask at −5 to 0° C. Thereafter, 25 g of 2-aminoethanol was added dropwise at a rate of 190 g/h. The resultant was heated to room temperature and aged for 12 hours. Then, while the mixture in the flask was heated to a temperature of 50° C., acetonitrile was removed under reduced pressure, and the resulting mixture was finally kept at a pressure of about 0.001 for 4 hours, to thereby produce about 1,850 g of 2-(acetoacetamido)ethanol. the mixture was cooled so that the temperature in the flask was lowered to −5 to 0° C In such a case, about 2 hours after the commencement of dropwise addition was further added dropwise addition During the addition cooling The resultant was heated to room temperature and aged for 12 hours was removed under reduced pressure

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 23 ml (0.38 mmol) of ethanolamine were added dropwise to a solution of 30 g of diketene (0.36 mol) in 300 ml tetrahydrofuran at −5 to 0° C. After 1 h stirring at 0° C. no more starting material was detected by thin layer chromatography. The reaction mixture was evaporated and the residue purified by column chromatography. This gave 41.44 g (0.29 mol, 80% yield) as a white solid. The reaction mixture was evaporated the residue purified by column chromatography

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

Procedure: To a solution of diketene (42.1 g, 0.5 mol) in dichloromethane (100 ml), ethanolamine (30.5 g, 0.5 mol) was added dropwise at 10°-20.C with stirring, and the reaction was carried out at room temperature for 2 hrs. After pouring H2O (200 ml) into the reaction solution, an aqueous layer was separated, washed thrice with dichloromethane and was obtained N-(2-hydroxyethyl)-3-oxobutanamide as an aqueous solution. an aqueous layer was separated washed thrice with dichloromethane