1-[(4-chlorophenyl)methyl]piperazin-2-one

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

Procedure: A cold (0° C.) solution of tert-Butyl 4-(4-chlorobenzyl)-3-oxopiperazine-1-carboxylate (3.2 g, 9.9 mmol) in ethyl acetate (100 mL) was saturated with HCl gas. The resultant mixture was stirred at 0° C. for 1 h. The product mixture was concentrated under vacuum. The residue was treated with dichloromethane saturated with ammonia gas. The resultant chalky mixture was filtered, and the filtrate concentrated under vacuum. The residue was diluted with benzene and concentrated under vacuum to provide 1-(4-chlorobenzyl)-piperazin-2-one. The product mixture was concentrated under vacuum The residue was treated with dichloromethane saturated with ammonia gas The resultant chalky mixture was filtered the filtrate concentrated under vacuum The residue was diluted with benzene concentrated under vacuum

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

Procedure: A cold (0° C.) solution of tert-Butyl 4-(4-chlorobenzyl)-3-oxopiperazine-1-carboxylate (3.2 g, 9.9 mmol) in ethyl acetate (100 mL) was saturated with HCl gas. The resultant mixture was stirred at 0° C. for 1 h. The product mixture was concentrated under vacuum. The residue was treated with dichloromethane saturated with ammonia gas. The resultant chalky mixture was filtered, and the filtrate concentrated under vacuum. The residue was diluted with benzene and concentrated under vacuum to provide 1-(4-chlorobenzyl)-piperazin-2-one. The product mixture was concentrated under vacuum The residue was treated with dichloromethane saturated with ammonia gas The resultant chalky mixture was filtered the filtrate concentrated under vacuum The residue was diluted with benzene concentrated under vacuum