Reaktion #1995811

Reaktionsgleichung

1-(3-Trifluoromethyl-phenyl)-piperazine

(S)-2-Benzyloxycarbonylamino-pentanedioic acid 5-tert-butyl ester

TOTU

N-Methylmorpholine

→

desired product

Ausbeute 170.5%

(S)-4-Benzyloxycarbonylamino-5-oxo-5-[4-(3-trifluoromethyl-phenyl)-piperazin-1-yl]-pentanoic acid tert-butyl ester

Ausbeute 170.5%

Lösungsmittel

DMF

ethyl acetate

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGstirring
2. 2
   workup.WAITwas continued for 5 h
3. 3
   Waschenwashed with saturated sodium hydrogen carbonate solution
4. 4
   TrocknenDrying of the organic phase over sodium sulfate and evaporation of the solvents under reduced pressure
5. 5
   Sonstigeafforded a brownish powder that
6. 6
   Sonstigewas purified by chromatography over silica gel eluting with ethyl acetate/heptane 1

Vorschrift

2.53 g of (S)-2-Benzyloxycarbonylamino-pentanedioic acid 5-tert-butyl ester and 2.46 g of TOTU was dissolved in 15 ml of DMF. The, 3.29 ml of N-Methylmorpholine was added and the mixture was stirred for 30 min at RT. 1.72 g of 1-(3-Trifluoromethyl-phenyl)-piperazine was added and stirring was continued for 5 h. The mixture was diluted with ethyl acetate and washed with saturated sodium hydrogen carbonate solution. Drying of the organic phase over sodium sulfate and evaporation of the solvents under reduced pressure afforded a brownish powder that was purified by chromatography over silica gel eluting with ethyl acetate/heptane 1:2 to 100% ethyl acetate to give 7 g of the desired product.

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