ethyl 2-(4-hydroxy-2-oxopyrrolidin-1-yl)acetate

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:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of ethyl 4-hydroxy-2-oxo-1-pyrrolidineacetate (0.5 g) and glycinamide (0.6 g) was stirred under nitrogen at 80° C. for 4 hours. After cooling, the mixture was chromatographed on a silica gel column, by eluting with dichloromethane/methanol 7:3, affording the title compound (250 mg). After cooling the mixture was chromatographed on a silica gel column by eluting with dichloromethane/methanol 7:3

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of ethyl 4-hydroxy-2-oxo-1-pyrrolidineacetate (0.5 g) and glycinamide (0.6 g) was stirred under nitrogen at 80° C. for 4 hours. After cooling, the mixture was chromatographed on a silica gel column, by eluting with dichloromethane/methanol 7:3, affording the title compound (250 mg). After cooling the mixture was chromatographed on a silica gel column by eluting with dichloromethane/methanol 7:3

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 51.5 g. 4-trimethylsilyloxypyrrolidin-2-one in 500 ml. anhydrous acetonitrile are added 133 ml. ethyl bromoacetate. The solution is heated to 50° C. and 26.7 g. of 80% sodium hydride (dispersion in mineral oil) are slowly added in small amounts. When the addition is completed, the reaction mixture is heated under reflux for 30 minutes and then cooled to ambient temperature. To the reaction mixture obtained containing ethyl 2-(4-trimethylsilyloxypyrrolidin-2-on-1-yl)-acetate (b.p. 160° C./3 mm.Hg) are added 50 ml. 1 N hydrochloric acid. The reaction mixture is stirred for 30 minutes and then evaporated to dryness. The residue obtained is chromatographed on a silica gel column, using ethyl acetate as the elution agent, 45 g. ethyl 2-(4-hydroxypyrrolidin-2-on-1-yl)-acetate being obtained; b.p. 180° C./0.8 mm.Hg; Rf 0.17 (silica gel; eluant ethyl acetate). When the addition the reaction mixture is heated under reflux for 30 minutes cooled to ambient temperature To the reaction mixture obtained are added 50 ml evaporated to dryness The residue obtained is chromatographed on a silica gel column

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

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 51.5 g. 4-trimethylsilyloxypyrrolidin-2-one in 500 ml. anhydrous acetonitrile are added 133 ml. ethyl bromoacetate. The solution is heated to 50° C. and 26.7 g. of 80% sodium hydride (dispersion in mineral oil) are slowly added in small amounts. When the addition is completed, the reaction mixture is heated under reflux for 30 minutes and then cooled to ambient temperature. To the reaction mixture obtained containing ethyl 2-(4-trimethylsilyloxypyrrolidin-2-on-1-yl)-acetate (b.p. 160° C./3 mm.Hg) are added 50 ml. 1 N hydrochloric acid. The reaction mixture is stirred for 30 minutes and then evaporated to dryness. The residue obtained is chromatographed on a silica gel column, using ethyl acetate as the elution agent, 45 g. ethyl 2-(4-hydroxypyrrolidin-2-on-1-yl)-acetate being obtained; b.p. 180° C./0.8 mm.Hg; Rf 0.17 (silica gel; eluant ethyl acetate). When the addition the reaction mixture is heated under reflux for 30 minutes cooled to ambient temperature To the reaction mixture obtained are added 50 ml evaporated to dryness The residue obtained is chromatographed on a silica gel column

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

Procedure: A solution of 7.1 g ethyl 4-hydroxy-2-oxo-1-pyrrolidineacetate obtained in Example 12, in 7.1 ml ammonia solution (d25 =0.90) is stirred at ambient temperature for 15 h. It is then diluted with 140 ml acetone and the mixture is stirred at ambient temperature until the gum that precipitates solidifies into white crystals. On filtering in vacuo and drying, 4-hydroxy-2-oxo-1-pyrrolidineacetamide is obtained, m.p. 160°-162° C. that precipitates On filtering in vacuo drying

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

Procedure: A solution of 7.1 g ethyl 4-hydroxy-2-oxo-1-pyrrolidineacetate obtained in Example 12, in 7.1 ml ammonia solution (d25 =0.90) is stirred at ambient temperature for 15 h. It is then diluted with 140 ml acetone and the mixture is stirred at ambient temperature until the gum that precipitates solidifies into white crystals. On filtering in vacuo and drying, 4-hydroxy-2-oxo-1-pyrrolidineacetamide is obtained, m.p. 160°-162° C. that precipitates On filtering in vacuo drying

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

Procedure: A solution of 0.16 g ethyl 2-oxo-4-(tetrahydropyran-2-yl)-1-pyrrolidineacetate is dissolved in 5 ml ethanol containing 16 mg pyridinium p-toluenesulphonate. The mixture is heated 4 h at 35°, the ethanol is evaporated and the residue chromatographed on silica. The title compound is obtained as a colourless oil in 62% yield. The mixture is heated 4 h at 35° the ethanol is evaporated the residue chromatographed on silica

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

Procedure: A solution of 0.16 g ethyl 2-oxo-4-(tetrahydropyran-2-yl)-1-pyrrolidineacetate is dissolved in 5 ml ethanol containing 16 mg pyridinium p-toluenesulphonate. The mixture is heated 4 h at 35°, the ethanol is evaporated and the residue chromatographed on silica. The title compound is obtained as a colourless oil in 62% yield. The mixture is heated 4 h at 35° the ethanol is evaporated the residue chromatographed on silica