Reaktion #44986

Reaktionsgleichung

Methyl trans-4-[{2-[(t-butoxycarbonyl)amino]ethyl}-(chloroacetyl)amino]cyclohexanecarboxylate

sodium hydride

ammonium chloride

water

→

t-butyl 4-[trans-4-(methoxycarbonyl)cyclohexyl]-3-oxopiperazine-1-carboxylate

Ausbeute 59.7%

Lösungsmittel

N,N-dimethylacetamide

—

oil

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturunder ice-cooling
2. 2
   Temperatursame cooling conditions
3. 3
   Temperaturcooling
4. 4
   Extraktionthe mixture is extracted with ethyl acetate
5. 5
   WaschenThe organic layer is washed with water and saturated brine successively
6. 6
   Trocknendried over sodium sulfate
7. 7
   Sonstigeevaporated
8. 8
   Sonstigeto remove the solvent under reduced pressure
9. 9
   SonstigeThe resulting residue is purified by silica gel column chromatography (eluent: n-hexane/ethyl acetate=1/1)

Vorschrift

Methyl trans-4-[{2-[(t-butoxycarbonyl)amino]ethyl}-(chloroacetyl)amino]cyclohexanecarboxylate (560 mg) obtained in Reference Example 71(2) is dissolved in N,N-dimethylacetamide (5 ml), and 60% sodium hydride in oil (119 mg) is added thereto under ice-cooling. The reaction solution is then stirred for 0.5 hours under the same cooling conditions. Saturated aqueous ammonium chloride solution and water are poured to the reaction solution successively under ice-cooling, and the mixture is extracted with ethyl acetate. The organic layer is washed with water and saturated brine successively, dried over sodium sulfate and evaporated to remove the solvent under reduced pressure. The resulting residue is purified by silica gel column chromatography (eluent: n-hexane/ethyl acetate=1/1) to give t-butyl 4-[trans-4-(methoxycarbonyl)cyclohexyl]-3-oxopiperazine-1-carboxylate (302 mg).

Quelle