Hydrochloric Acid → Piperazin-1-ol dihydrochloride

To 1-formyl-4-hydroxypiperazine (5.0 g) is added 3N hydrochloric acid (50 ml) and the mixture is heated at 77°-87° C. with stirring for 20 minutes and water is removed from the mixture under reduced pressure to yield a pale yellow residue. After washing with ethanol, the residue is crystallized from a mixture of water and ethanol to give 1-hydroxypiperazine dihydrochloride (5.0 g) as light brown prisms, m.p. 164°-175° C. (decomposition).

1. temperaturethe mixture is heated at 77°-87° C.
2. customwater is removed from the mixture under reduced pressure
3. customto yield a pale yellow residue
4. washAfter washing with ethanol
5. customthe residue is crystallized from a mixture of water and ethanol

ORD record

ord-25f1f144415f414cb9f09abd371778aa

Source dataset

uspto-grants-1987_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04686221