Hydrochloric Acid → 1-(3-Aminopropyl)-4-methylpiperazine

Participants

Reaction Steps

A solution of N-(3-(4-methylpiperazin-1-yl)propyl)phthalimide (6.2 g, 21.6 mM) and hydrazine monohydrate (1.13 g, 26 mM) in ethanol (60 mL) and methanol (60 mL) was refluxed for 4 hours. After cooling to room temperature, concentrated HCl (2.4 mL) was added and the mixture heated under reflux for another hour. After removing the solvent, water (100 mL) was added, the mixture stirred and insoluble material removed by filtration. Solid K2CO3 (1.2 eq) and CH2Cl2 (100 mL) was added to the aqueous layer; the mixture stirred, and was then filtered. The organic layer was washed with water (3×20 mL). The combined aqueous layers were washed with Et2O. Water was removed from the organic layers, which were then dried and evaporated to give 1-(3-aminopropyl)-4-methylpiperazine as an oil in 39% yield. 1H NMR (CDCl3): δ=1.55 (m, 2H, CH2), 2.20 (s, 3H, CH3), 2.34 (t, 2H, CH2), 2.67 (t, 2H, CH2). MS (ES+): 157.9.

Provenance & Evidence