3-benzyl-5,5-dimethylimidazolidine-2,4-dione

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

Procedure: 5,5-Dimethyl hydantoin (5.15 g, 0.039 mole) was added to a suspension of sodium hydride (1.87 g, 50% oil dispersion) in dry dimethylformamide (50 ml) and the mixture stirred and heated at 50° C. until evolution of hydrogen ceased. The solution was cooled and benzyl chloride (4.94 ml, 1.1 equivalents) was added and the mixture heated at 50° C. for 11/2 hours. The dimethylformamide was removed under reduced pressure and the residue partitioned between ether and brine. The ethereal extracts were combined, washed with water, dried (MgSO4) and the solvent evaporated to yield the title compound as a white crystalline solid m.p. 100°-102° C. Yield=8.0 g=91%. The solution was cooled The dimethylformamide was removed under reduced pressure the residue partitioned between ether and brine washed with water dried (MgSO4) the solvent evaporated

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

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

Procedure: To a stirred solution of 3-benzyl-5,5-dimethylhydantoin (9.5 g, 43.6 mmole) in acetone (100 mL) at room temperature were added potassium carbonate (8.4 g, 60.9 mmole) and propargyl bromide (7.1 g of 80 % in toluene, 47.7 mmole). The reaction mixture was refluxed for 16 hr; cooled to room temperature and the solid was filtered off by suction-filtration. The filtrate was concentrated and the resultant residue was diluted with ethyl acetate and washed with water and brine. The organic layer was dried over sodium sulfate. After evaporation, a yellow crude oil was obtained. A pure product, 5.5 g (yield=50%) of 3-benzyl-1-propargyl-5,5-dimethylhydantoin as a yellow oil, was obtained by column chromatography on silica gel eluting with ethyl acetate:hexane (1:1 ). The reaction mixture was refluxed for 16 hr the solid was filtered off by suction-filtration The filtrate was concentrated the resultant residue was diluted with ethyl acetate washed with water and brine The organic layer was dried over sodium sulfate After evaporation a yellow crude oil was obtained

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

Procedure: To the stirred solution of 5,5-dimethylhydantoin (7 g, 54.7 mmole) in dry acetone (150 mL) under nitrogen were added potassium carbonate (10.6 g, 76.8 mmole) and benzylbromide (11.2 g, 65.9 mmole) at room temperature. The reaction mixture was refluxed for 20 hr. The reaction mixture was cooled to room temperature and the solid was filtered off by suction filtration. The titrate was concentrated on a rotary evaporator to give a residue. The residue was diluted with ethyl acetate and washed with water and brine, dried over sodium sulfate and evaporated to give 10.9 g (yield=91.3 %) of 3-benzyl-5,5-dimethylhydantoin as a white solid, mp=101°-104° C. This intermediate was subjected to the next step without further purification. The reaction mixture was refluxed for 20 hr the solid was filtered off by suction filtration The titrate was concentrated on a rotary evaporator to give a residue washed with water and brine dried over sodium sulfate evaporated

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

Procedure: To the stirred solution of 5,5-dimethylhydantoin (7 g, 54.7 mmole) in dry acetone (150 mL) under nitrogen were added potassium carbonate (10.6 g, 76.8 mmole) and benzylbromide (11.2 g, 65.9 mmole) at room temperature. The reaction mixture was refluxed for 20 hr. The reaction mixture was cooled to room temperature and the solid was filtered off by suction filtration. The titrate was concentrated on a rotary evaporator to give a residue. The residue was diluted with ethyl acetate and washed with water and brine, dried over sodium sulfate and evaporated to give 10.9 g (yield=91.3 %) of 3-benzyl-5,5-dimethylhydantoin as a white solid, mp=101°-104° C. This intermediate was subjected to the next step without further purification. The reaction mixture was refluxed for 20 hr the solid was filtered off by suction filtration The titrate was concentrated on a rotary evaporator to give a residue washed with water and brine dried over sodium sulfate evaporated

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

Procedure: To the stirred solution of 5,5-dimethylhydantoin (7 g, 54.7 mmole) in dry acetone (150 mL) under nitrogen were added potassium carbonate (10.6 g, 76.8 mmole) and benzylbromide (11.2 g, 65.9 mmole) at room temperature. The reaction mixture was refluxed for 20 hr. The reaction mixture was cooled to room temperature and the solid was filtered off by suction filtration. The titrate was concentrated on a rotary evaporator to give a residue. The residue was diluted with ethyl acetate and washed with water and brine, dried over sodium sulfate and evaporated to give 10.9 g (yield=91.3 %) of 3-benzyl-5,5-dimethylhydantoin as a white solid, mp=101°-104° C. This intermediate was subjected to the next step without further purification. The reaction mixture was refluxed for 20 hr the solid was filtered off by suction filtration The titrate was concentrated on a rotary evaporator to give a residue washed with water and brine dried over sodium sulfate evaporated

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

Procedure: 5,5-Dimethyl hydantoin (5.15 g, 0.039 mole) was added to a suspension of sodium hydride (1.87 g, 50% oil dispersion) in dry dimethylformamide (50 ml) and the mixture stirred and heated at 50° C. until evolution of hydrogen ceased. The solution was cooled and benzyl chloride (4.94 ml, 1.1 equivalents) was added and the mixture heated at 50° C. for 11/2 hours. The dimethylformamide was removed under reduced pressure and the residue partitioned between ether and brine. The ethereal extracts were combined, washed with water, dried (MgSO4) and the solvent evaporated to yield the title compound as a white crystalline solid m.p. 100°-102° C. Yield=8.0 g=91%. The solution was cooled The dimethylformamide was removed under reduced pressure the residue partitioned between ether and brine washed with water dried (MgSO4) the solvent evaporated