1-Methylpiperazine → HCID 18698346, compound

Participants

Reaction Steps

(1-Aminocyclopentyl)(4-methyl-1-piperazinyl)methanone dihydrochloride ##STR204## 1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (2.49 g, 13.0 mmol) was added portionwise to a cooled (4° C.) solution of hydroxybenzotriazole hydrate (1.49 g, 11.0 mmol) and 1-[(tert-butoxycarbonyl)amino]cyclopentanecarboxylic acid (2.29 g, 10.0 mmol) in DMF (15 ml), and the mixture stirred for 30 min. N-Methylpiperazine (1.10 g, 11.0 mmol) was added, the reaction stirred for 30 min. allowed to warm to room temperature and stirring continued for a further 17 h. The reaction mixture was evaporated in vacuo, and the residual yellow oil partitioned between saturated Na2CO3 solution and EtOAc. The layers were separated, the aqueous phase extracted with EtOAc, and the combined organic solutions dried (MgSO4) and concentrated in vacuo. The residual solid was pre-adsorbed onto silica gel and purified by column chromatography upon silica gel using an elution gradient of CH2Cl2 -MeOH-0.880 NH3 (97.5:2.5:0.25 to 90:10:1) and triturated with Et2O to afford tert-butyl 1-[(4-methyl-1-piperazinyl)carbonyl]cyclopentylcarbamate (2.31 g, 7.4 mmol) as a crystalline solid.

Provenance & Evidence