Reaktion #2129299

Reaktionsgleichung

Na2S2O3

tert-butyl 1-(4-fluoro-3-nitrophenyl)-3-isopropyl-1H-pyrazole-5-carboxylate

LiOH

H2O2

→

tert-butyl 1-(4-hydroxy-3-nitrophenyl)-3-isopropyl-1H-pyrazole-5-carboxylate

Ausbeute 37.0%

Lösungsmittel

Acetic acid

THF water

Reaktionsbedingungen

Aufarbeitung

1. 1
   ExtraktionThe solution was extracted with EtOAc
2. 2
   Waschenthe organic layer was washed with brine
3. 3
   Trocknendried (MgSO4)
4. 4
   Einengenconcentrated in vacuo
5. 5
   Sonstigepurified by silica gel column chromatography (EtOAc/hexanes)

Vorschrift

To a solution of tert-butyl 1-(4-fluoro-3-nitrophenyl)-3-isopropyl-1H-pyrazole-5-carboxylate (0.74 g, 2.1 mmol) in THF/water (12 mL) was added LiOH (300 mg, 13 mmol) and H2O2 (30% wt, 0.96 mL). The reaction mixture was heated overnight at 60° C. Na2S2O3 solution was added until the peroxide test (starch-iodide paper) was negative. Acetic acid was added until the pH was 4-5. The solution was extracted with EtOAc and the organic layer was washed with brine, dried (MgSO4), concentrated in vacuo and purified by silica gel column chromatography (EtOAc/hexanes) to obtain tert-butyl 1-(4-hydroxy-3-nitrophenyl)-3-isopropyl-1H-pyrazole-5-carboxylate (0.27 g, 37% yield). MS (ESI) m/z: 348.3 (M+H+).

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