Hydrochloric Acid → Piperazin-1-ol dihydrochloride

3N Hydrochloric acid (50 ml) was added to 1-formyl-4-hydroxypiperazine (5.0 g) and the mixture was stirred at 77° to 87° C. for 20 minutes. After stirring, water was distilled off under reduced pressure to give a pale yellow residue, which was washed with ethanol and recrystallized from a mixed solvent of water-ethanol to give 1-hydroxypiperazine dihydrochloride (5.0 g) as light brown prisms, m.p. 164°-175° C. (dec.).

1. stirringAfter stirring
2. distillationwater was distilled off under reduced pressure
3. customto give a pale yellow residue, which
4. washwas washed with ethanol
5. customrecrystallized from a mixed solvent of water-ethanol

ORD record

ord-72b97ece12064e748be84f3235d74875

Source dataset

uspto-grants-1989_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04853469