Reaktion #7862

Reaktionsgleichung

NaHCO3

4-fluoro-2-nitrophenol

tin(II) chloride dihydrate

→

2-amino-4-fluorophenol

Lösungsmittel

MeOH

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe reaction mixture was heated
2. 2
   Temperaturat reflux
3. 3
   workup.ADDITIONpoured over ice
4. 4
   ExtraktionThe aqueous layer was extracted with EtOAc (2×200 mL)
5. 5
   Waschenthe combined extracts washed with brine
6. 6
   Trocknendried over MgSO4
7. 7
   Filtrationfiltered
8. 8
   Einengenconcentrated in vacuo

Vorschrift

To a stirred solution of 4-fluoro-2-nitrophenol (4.05 g, 25.8 mmol) in MeOH (200 mL) was added tin(II) chloride dihydrate (17.47 g, 77.4 mmol). The reaction mixture was heated at reflux and monitored by LC/MS. When significant reduction was complete, the reaction mixture was cooled to rt, poured over ice, and made basic (pH 9) with 50% saturated NaHCO3. The aqueous layer was extracted with EtOAc (2×200 mL) and the combined extracts washed with brine, dried over MgSO4, filtered, and concentrated in vacuo to give 2-amino-4-fluorophenol as a grayish green solid. 1H NMR (CDCl3, 300 MHz) δ 6.64 (dd, 1H), 6.47 (dd, 1H), 6.33 (dt, 1H), 4.48 (br s, 1H), 3.78 (br s, 2H).

Quelle