2,2-dimethylimidazolidin-4-one

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: The same procedure of Example 10, starting from 4-hydroxy-2-oxo-1-pyrrolidineacetic acid and 2,2-dimethyl-4-imidazolidinone, afforded the title compound, m.p. 250° C. (dec).

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

Procedure: The same procedure of Example 10, starting from 4-hydroxy-2-oxo-1-pyrrolidineacetic acid and 2,2-dimethyl-4-imidazolidinone, afforded the title compound, m.p. 250° C. (dec).

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

Procedure: An ice cold solution of 2-oxo-1-pyrrolidineacetic acid (2.2 g) and triethylamine (2.15 ml) in dimethylformamide (10 ml) was treated dropwise while stirring with butyl chloroformate (1.95 ml). After stirring at 0° C. for 30 minutes, 2,2-dimethyl-4-imidazolidinone (1.75 g) was added at once, and stirring was continued at room temperature overnight. After evaporation under reduced pressure the residue was chromatographed on a silica gel column, eluting with dichloromethane/methanol 1:1. The selected fractions were collected and evaporated to give an oil which was washed twice with ethyl acetate. The residue was crystallized from ethyl acetate, to give the title compound as a white powder, m.p. 214°-217° C. (decomp.). stirring was continued at room temperature overnight After evaporation under reduced pressure the residue was chromatographed on a silica gel column eluting with dichloromethane/methanol 1:1 The selected fractions were collected evaporated to give an oil which was washed twice with ethyl acetate The residue was crystallized from ethyl acetate

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

Procedure: An ice cold solution of 2-oxo-1-pyrrolidineacetic acid (2.2 g) and triethylamine (2.15 ml) in dimethylformamide (10 ml) was treated dropwise while stirring with butyl chloroformate (1.95 ml). After stirring at 0° C. for 30 minutes, 2,2-dimethyl-4-imidazolidinone (1.75 g) was added at once, and stirring was continued at room temperature overnight. After evaporation under reduced pressure the residue was chromatographed on a silica gel column, eluting with dichloromethane/methanol 1:1. The selected fractions were collected and evaporated to give an oil which was washed twice with ethyl acetate. The residue was crystallized from ethyl acetate, to give the title compound as a white powder, m.p. 214°-217° C. (decomp.). stirring was continued at room temperature overnight After evaporation under reduced pressure the residue was chromatographed on a silica gel column eluting with dichloromethane/methanol 1:1 The selected fractions were collected evaporated to give an oil which was washed twice with ethyl acetate The residue was crystallized from ethyl acetate

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

Procedure: To a stirred, ice-cold solution of N-(benzyloxycarbonyl)alanine (6.7 g) and 2,2-dimethyl-4-imidazolidinone (3.42 g) in 100 ml of THF, a solution of DCC (6.2 g) in 50 ml of THF was added dropwise during 15 minutes. The suspension was stirred at 0° C. for 2 hours and at room temperature for an additional 2 hours. The insoluble material was filtered off. The solvent was evaporated under reduced pressure. Crystallization of the residue from isopropanol gave the title product as a white powder m.p. 170°-171° C. The insoluble material was filtered off The solvent was evaporated under reduced pressure Crystallization of the residue from isopropanol

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

Procedure: To a stirred, ice-cold solution of N-(benzyloxycarbonyl)alanine (6.7 g) and 2,2-dimethyl-4-imidazolidinone (3.42 g) in 100 ml of THF, a solution of DCC (6.2 g) in 50 ml of THF was added dropwise during 15 minutes. The suspension was stirred at 0° C. for 2 hours and at room temperature for an additional 2 hours. The insoluble material was filtered off. The solvent was evaporated under reduced pressure. Crystallization of the residue from isopropanol gave the title product as a white powder m.p. 170°-171° C. The insoluble material was filtered off The solvent was evaporated under reduced pressure Crystallization of the residue from isopropanol

Conditions: temp:20.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To an ice-cold solution of N-(benzyloxycarbonyl) glycine (9 g) and 2,2-dimethyl-4-imidazolidinone (5 g) in tetrahydrofuran (THF) (150 ml) a solution of dicyclohexylcarbodiimide (DCC) (9 g) in THF (50 ml) was added dropwise. After stirring for 3 hours at 20° C., the precipitate was filtered off, the filtrate was evaporated to dryness and the residue was crystallized from 2-propanol affording 12 g of the title compound, m.p. 135°-136° C. the precipitate was filtered off the filtrate was evaporated to dryness the residue was crystallized from 2-propanol affording 12 g of the title compound, m.p. 135°-136° C.

Conditions: temp:20.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To an ice-cold solution of N-(benzyloxycarbonyl) glycine (9 g) and 2,2-dimethyl-4-imidazolidinone (5 g) in tetrahydrofuran (THF) (150 ml) a solution of dicyclohexylcarbodiimide (DCC) (9 g) in THF (50 ml) was added dropwise. After stirring for 3 hours at 20° C., the precipitate was filtered off, the filtrate was evaporated to dryness and the residue was crystallized from 2-propanol affording 12 g of the title compound, m.p. 135°-136° C. the precipitate was filtered off the filtrate was evaporated to dryness the residue was crystallized from 2-propanol affording 12 g of the title compound, m.p. 135°-136° C.

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

Procedure: (1) To an ice-cold stirred solution of 2,2-dimethyl-4-imidazolidinone (7 g) and potassium carbonate (12.8 g) in water (80 ml), bromoacetyl bromide (5.4 ml) was added dropwise. The reaction mixture was stirred at the same temperature for 1 hour, then at room temperature for 2 hours. The obtained suspension was extracted three times with ethyl acetate and the organic phase was washed with 3% hydrochloric acid, dried and evaporated under reduced pressure to give a residue which was crystallized from xylene to afford 1-(2-bromoacetyl)-2,2-dimethyl-4-imidazolidinone as a white crystalline powder, m.p. 137°-138° C. at room temperature for 2 hours The obtained suspension was extracted three times with ethyl acetate the organic phase was washed with 3% hydrochloric acid dried evaporated under reduced pressure to give a residue which was crystallized from xylene

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

Procedure: (1) To an ice-cold stirred solution of 2,2-dimethyl-4-imidazolidinone (7 g) and potassium carbonate (12.8 g) in water (80 ml), bromoacetyl bromide (5.4 ml) was added dropwise. The reaction mixture was stirred at the same temperature for 1 hour, then at room temperature for 2 hours. The obtained suspension was extracted three times with ethyl acetate and the organic phase was washed with 3% hydrochloric acid, dried and evaporated under reduced pressure to give a residue which was crystallized from xylene to afford 1-(2-bromoacetyl)-2,2-dimethyl-4-imidazolidinone as a white crystalline powder, m.p. 137°-138° C. at room temperature for 2 hours The obtained suspension was extracted three times with ethyl acetate the organic phase was washed with 3% hydrochloric acid dried evaporated under reduced pressure to give a residue which was crystallized from xylene