Stannous chloride dihydrate → 2-Amino-4-fluorophenol

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).

1. temperatureThe reaction mixture was heated
2. temperatureat reflux
3. additionpoured over ice
4. extractionThe aqueous layer was extracted with EtOAc (2×200 mL)
5. washthe combined extracts washed with brine
6. dry with materialdried over MgSO4
7. filtrationfiltered
8. concentrationconcentrated in vacuo

ORD record

ord-155edca81d244fa58d3afef51264be52

Source dataset

uspto-grants-2006_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07087601B2