414910-15-9

59878-57-8

The general procedure for the synthesis of 1-cyclopropanecarbonylpiperazine from tert-butyl 4-(cyclopropanecarbonyl)piperazine-1-carboxylate was as follows: 1-tert-butoxycarbonyl-4-(cyclopropanecarbonyl)piperazine (190 mg, 0.75 mmol) was dissolved in dichloromethane (5 mL), followed by slow addition of trifluoroacetic acid (1 mL). The reaction mixture was stirred at room temperature and the progress of the reaction was monitored by thin layer chromatography (TLC) until complete consumption of the ingredients. Upon completion of the reaction, the reaction mixture was washed with saturated sodium bicarbonate solution (3 × 10 mL) to neutralize the acid. The organic phase was separated, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure to afford 112 mg (97% yield) of 1-cyclopropanecarbonylpiperazine as a light yellow solid, which was used directly in the next step of the reaction.