Reaktion #77314

Reaktionsgleichung

(S)-4-carbobenzyloxy-1-(4,5-dichloro-2-nitrophenyl)-piperazine-2-carboxylic acid

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title compound

Ausbeute 120.2%

(S)-8,9-Dichloro-2,3,4,4a-Tetrahydro-1H-Pyrazino[1,2-a]Quinoxalin-5(6H)-One

Ausbeute 120.2%

Lösungsmittel

acetic acid

Reaktionsbedingungen

Aufarbeitung

1. 1
   Einengenconcentrated under reduced pressure (1-2 mm, <40° C.) to a gray-black residue
2. 2
   WaschenThe combined ethyl acetate filtrates are washed with 100 mL of 1N HCl, 200 mL of water (2×), 100 mL of brine
3. 3
   Trocknendried over MgSO4
4. 4
   FiltrationFiltration and concentration of the solvent
5. 5
   Sonstigegave a semi-solid material that
6. 6
   Sonstigeis crystallized from hexane

Vorschrift

To a solution of 1.5 g (S)-4-carbobenzyloxy-1-(4,5-dichloro-2-nitrophenyl)-piperazine-2-carboxylic acid in 40 mL of acetic acid is added 1.2 g of iron powder. With good stirring, the mixture is heated at 60° C. for 2 hours, then concentrated under reduced pressure (1-2 mm, <40° C.) to a gray-black residue. This material was slurried with 100 mL of ethyl acetate (2×). The combined ethyl acetate filtrates are washed with 100 mL of 1N HCl, 200 mL of water (2×), 100 mL of brine and dried over MgSO4. Filtration and concentration of the solvent gave a semi-solid material that is crystallized from hexane to afford 1.08 g (80.6%) of title compound as a white solid, mp 174-6° C.

Quelle