Ethanol → 5-Amino-2-chloro-4-fluorophenol

A mixture of 2-chloro-4-fluoro-5-nitrophenol (28.6 g, 0.150 mol), reduced iron (41.6 g, 0.745 mol), calcium chloride (8.28 g, 74.6 mmol) and ethanol (540 mL)/water (60 mL) was stirred with heating under reflux for 3.5 hr. The reaction mixture was filtered through celite, the filtrate was concentrated under reduced pressure, and ethyl acetate (700 mL) was added to the residue. The solution was washed with water (200 mL) and saturated brine (100 mL), and dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane/ethyl acetate=95/5→50/50) to give the title compound (19.3 g, 80%) as a brown powder.

1. temperaturewith heating
2. temperatureunder reflux for 3.5 hr
3. filtrationThe reaction mixture was filtered through celite
4. concentrationthe filtrate was concentrated under reduced pressure, and ethyl acetate (700 mL)
5. additionwas added to the residue
6. washThe solution was washed with water (200 mL) and saturated brine (100 mL)
7. dry with materialdried over anhydrous magnesium sulfate
8. concentrationconcentrated under reduced pressure
9. customThe residue was purified by silica gel column chromatography (hexane/ethyl acetate=95/5→50/50)

ORD record

ord-823bce5d2acc4fe281de3cc204239c6a

Source dataset

uspto-grants-2013_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08344135B2