Reaktion #78088

Reaktionsgleichung

tert-butyl 1-piperazinecarboxylate

3-fluoronitrobenzene

water

→

3-(1-(t-butoxycarbonyl)piperazin-4-yl)aniline

Lösungsmittel

NMP

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwas added
2. 2
   Extraktionthe mixture was extracted with ethyl acetate (2×10 ml)
3. 3
   ExtraktionThe organic extract
4. 4
   Trocknenwas dried over sodium sulfate
5. 5
   Sonstigethe solvent was removed under reduced pressure
6. 6
   SonstigeThe residue was purified by column-chromatography
7. 7
   workup.ADDITIONa mixture of ethyl acetate and petroleum ether (1:1 v/v) as the eluents

Vorschrift

A mixture of tert-butyl 1-piperazinecarboxylate (4 g, 21.5 mmol) and 3-fluoronitrobenzene (2.3 ml, 21.5 mmol) in anhydrous NMP (5 ml) was heated to 120° C. for 3 days. After cooling water (25 ml) was added and the mixture was extracted with ethyl acetate (2×10 ml). The organic extract was dried over sodium sulfate and the solvent was removed under reduced pressure. The residue was purified by column-chromatography using successively petroleum ether and a mixture of ethyl acetate and petroleum ether (1:1 v/v) as the eluents. Yield of t-butyl 4-(3-nitrophenyl)-1-piperazinecarboxylate: 1.34 g (20%). This intermediate was quantitatively hydrogenated to 2g in ethanol at ambient pressure using Pd (5% on activated carbon) as the catalyst.

Quelle