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

Temperature

90 °C

A suspension of 2-chloro-4-fluoro-5-nitrophenol (21.8 g, 124 mmol), calcium chloride (30.6 g, 248 mmol) and reduced iron (20.8 g, 372 mmol) in ethanol (500 mL)/water (50 mL) was stirred with heating at 90° C. for 4 hr. After the reaction mixture was cooled to room temperature, the insoluble material was filtered off through a pad filled with celite, and washed with ethyl acetate. The filtrate and the washing fluid were combined, and concentrated under reduced pressure. The obtained residue was diluted with ethyl acetate (500 mL), washed with water (250 mL×2), 5% aqueous sodium hydrogen carbonate solution (250 mL×2) and saturated brine (250 mL), and dried over anhydrous sodium sulfate. The insoluble material was filtered off, and the filtrate was concentrated under reduced pressure to give the title compound (15.5 g, 77%) as a black powder. This was used for the next reaction without further purification.

1. temperatureAfter the reaction mixture was cooled to room temperature
2. filtrationthe insoluble material was filtered off through a pad
3. additionfilled with celite
4. washwashed with ethyl acetate
5. concentrationconcentrated under reduced pressure
6. additionThe obtained residue was diluted with ethyl acetate (500 mL)
7. washwashed with water (250 mL×2), 5% aqueous sodium hydrogen carbonate solution (250 mL×2) and saturated brine (250 mL)
8. dry with materialdried over anhydrous sodium sulfate
9. filtrationThe insoluble material was filtered off
10. concentrationthe filtrate was concentrated under reduced pressure

ORD record

ord-7b39e476771c441dbfacf4ac1b0d6799

Source dataset

uspto-grants-2013_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08344135B2