Reaktion #1453461

Reaktionsgleichung

4-methyl-3-nitro-benzoic acid

N-butoxycarbonyl-piperazine

triethylamine

TBTU

HOAt

→

4-(4-methyl-3-nitrobenzoyl)-piperazine-1-carboxylic acid tert-butyl ester

Lösungsmittel

water

DMF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Extraktionextracted twice with ethyl acetate
2. 2
   WaschenThe organic layer is washed with water
3. 3
   Trocknenbrine, dried over magnesium sulfate
4. 4
   Sonstigeevaporated in vacuo
5. 5
   SonstigeThe residue is purified with silica gel column chromatography (n-hexane:ethyl acetate=5:1)

Vorschrift

To a solution of 4-methyl-3-nitro-benzoic acid (300 mg, 2.76 mmol), N-butoxycarbonyl-piperazine (340 mg, 1.83 mmol) in DMF (3.0 mL), triethylamine (300 μL, 3.59 mmol), TBTU (800 mg, 2.49 mmol) and HOAt (270.5 mg, 1.99 mmol) are added and stirred at room temperature for 24 hours. The mixture is poured into water and extracted twice with ethyl acetate. The organic layer is washed with water and then brine, dried over magnesium sulfate, and evaporated in vacuo. The residue is purified with silica gel column chromatography (n-hexane:ethyl acetate=5:1) to afford 4-(4-methyl-3-nitrobenzoyl)-piperazine-1-carboxylic acid tert-butyl ester as a colorless solid.

Quelle