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

A solution of N-(3-(4-methylpiperazin-1-yl)propyl)phthalimide and hydrazine monohydrate in ethanol and methanol was refluxed for 4 hours. After cooling to room temperature, concentrated HCl was added and the mixture heated under reflux for another hour. After removing the solvent, water was added, the mixture stirred, and insoluble material removed by filtration. Solid K2CO3 and CH2Cl2 were added to the aqueous layer, the mixture stirred, and was then filtered. The organic layer was washed with water. The combined aqueous layers were washed with Et2O. Water was removed from the organic layers, they were then dried and evaporated to give 1-(3-aminopropyl)-4-methylpiperazine as an oil. A reference for this synthesis is Hou et al., “Efficient syntheses of oncinotine and neooncinotine,” J. Org. Chem. 69(18):6094-9, 2004, which is incorporated by reference herein.

1. temperaturethe mixture heated
2. temperatureunder reflux for another hour
3. customAfter removing the solvent, water
4. additionwas added
5. custominsoluble material removed by filtration
6. additionSolid K2CO3 and CH2Cl2 were added to the aqueous layer
7. stirringthe mixture stirred
8. filtrationwas then filtered
9. washThe organic layer was washed with water
10. washThe combined aqueous layers were washed with Et2O
11. customWater was removed from the organic layers, they
12. customwere then dried
13. customevaporated

ORD record

ord-3f7283a1ca184e8d80b7f3d995ff3bb3

Source dataset

uspto-grants-2013_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08518885B2