Reaktion #1437537

Reaktionsgleichung

3-(S)-phenethyl-piperazine-2,5-dione

lithium aluminum hydride

sodium sulfate decahydrate

hydrogen

→

2-(S)-phenethyl-piperazine

Ausbeute 90.8%

Lösungsmittel

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturReflux the resulting suspension for an hour
2. 2
   Filtrationfilter
3. 3
   WaschenWash the solids with THF several times
4. 4
   EinengenCombine the filtrates, concentrate
5. 5
   Sonstigerecrystallize the residue with THF/pentane

Vorschrift

Add 3-(S)-phenethyl-piperazine-2,5-dione (2.5 g, 11 mmol) portionwise to lithium aluminum hydride (1.75 g, 46 mmol) in THF (46 mL). Reflux the resulting suspension for an hour and cool to 0° C. Add sodium sulfate decahydrate carefully until hydrogen evolution ceases and stir the mixture for an additional three hours at room temperature and filter. Wash the solids with THF several times. Combine the filtrates, concentrate, and recrystallize the residue with THF/pentane to afford 2-(S)-phenethyl-piperazine as white crystals (1.9 g, 90%): mp 114–115° C.; 1H NMR (CDCl3): δ1.58–1,70 (m, 2H), 2.41 (dd, 1H), 2.58–3.02 (m, 8H), 7.16–7.30 (m, 5H); MS (APCI) m/z (rel intensity) 191 (100).

Quelle