4-ethylpiperazin-2-one

Conditions: temp:55.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 2-oxopiperazine (1.07 g), iodoethane (1.72 g) and potassium carbonate (2.76 g) in acetonitrile (50 mL) was stirred at 55° C. for 3 hours. After cooling, the mixture was filtered and the filtrate was concentrated in vacuo. The residue was triturated with DCM and filtered and the filtrate was concentrated in vacuo. The residue was purified by chromatography on silica, eluting with a mixture of methanol and DCM with a gradient of 0-40% to give 4-ethylpiperazin-2-one (0.991 g) as a colourless oil. After cooling the mixture was filtered the filtrate was concentrated in vacuo The residue was triturated with DCM filtered the filtrate was concentrated in vacuo The residue was purified by chromatography on silica eluting with a mixture of methanol and DCM with a gradient of 0-40%

Conditions: temp:55.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 2-oxopiperazine (1.07 g), iodoethane (1.72 g) and potassium carbonate (2.76 g) in acetonitrile (50 mL) was stirred at 55° C. for 3 hours. After cooling, the mixture was filtered and the filtrate was concentrated in vacuo. The residue was triturated with DCM and filtered and the filtrate was concentrated in vacuo. The residue was purified by chromatography on silica, eluting with a mixture of methanol and DCM with a gradient of 0-40% to give 4-ethylpiperazin-2-one (0.991 g) as a colourless oil. After cooling the mixture was filtered the filtrate was concentrated in vacuo The residue was triturated with DCM filtered the filtrate was concentrated in vacuo The residue was purified by chromatography on silica eluting with a mixture of methanol and DCM with a gradient of 0-40%

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

Procedure: Sodium hydride (60% oil dispersion, 0.176 g) was added to a stirred solution of 4-ethyl-piperazin-2-one (Intermediate 176, 0.512 g) in anhydrous THF (10 mL) and the mixture was stirred at room temperature for 10 minutes. 3-Fluorobenzyl bromide (0.827 g) was added and stirring was continued for 2 hours. The solution was diluted with water and ethyl acetate and the organic layer was dried (Na2SO4) and filtered. The filtrate was concentrated in vacuo and the residue was purified by chromatography on silica, eluting with a mixture of methanol and DCM with a gradient of 0-5% to give 4-ethyl-1-(3-fluorobenzyl)piperazin-2-one (0.595 g) as a colourless oil. stirring was continued for 2 hours the organic layer was dried (Na2SO4) filtered The filtrate was concentrated in vacuo the residue was purified by chromatography on silica eluting with a mixture of methanol and DCM with a gradient of 0-5%

Conditions: temp:55.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 2-oxopiperazine (1.07 g), iodoethane (1.72 g) and potassium carbonate (2.76 g) in acetonitrile (50 mL) was stirred at 55° C. for 3 hours. After cooling, the mixture was filtered and the filtrate was concentrated in vacuo. The residue was triturated with DCM and filtered and the filtrate was concentrated in vacuo. The residue was purified by chromatography on silica, eluting with a mixture of methanol and DCM with a gradient of 0-40% to give 4-ethylpiperazin-2-one (0.991 g) as a colourless oil. After cooling the mixture was filtered the filtrate was concentrated in vacuo The residue was triturated with DCM filtered the filtrate was concentrated in vacuo The residue was purified by chromatography on silica eluting with a mixture of methanol and DCM with a gradient of 0-40%

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

Procedure: Sodium hydride (60% oil dispersion, 0.176 g) was added to a stirred solution of 4-ethyl-piperazin-2-one (Intermediate 176, 0.512 g) in anhydrous THF (10 mL) and the mixture was stirred at room temperature for 10 minutes. 3-Fluorobenzyl bromide (0.827 g) was added and stirring was continued for 2 hours. The solution was diluted with water and ethyl acetate and the organic layer was dried (Na2SO4) and filtered. The filtrate was concentrated in vacuo and the residue was purified by chromatography on silica, eluting with a mixture of methanol and DCM with a gradient of 0-5% to give 4-ethyl-1-(3-fluorobenzyl)piperazin-2-one (0.595 g) as a colourless oil. stirring was continued for 2 hours the organic layer was dried (Na2SO4) filtered The filtrate was concentrated in vacuo the residue was purified by chromatography on silica eluting with a mixture of methanol and DCM with a gradient of 0-5%