Phenol, 2,4-dichloro-5-nitro- → Phenol, 5-amino-2,4-dichloro-

Iron powder (4.03 g, 72.1 mmol) was added slowly to the solution of 2,4-dichloro-5-nitrophenol (3.00 g, 14.4 mmol) in acetic acid (100 ml). After stirring at room temperature overnight, the reaction mixture became milky with formation of a white precipitate. The precipitate was filtered off and the filtrate was concentrated to ca. 20 mL. The residue was diluted with water (100 mL) and neutralized by slow addition of sodium bicarbonate. The mixture was then extracted with methylene chloride (3×150 mL). The organic layer were combined, dried over sodium sulfate, filtered and concentrated to dryness to afford 5-amino-2,4-dichlorophenol (2.20 g, 86%) as a brown solid. 1H-NMR (DMSO-d6) 89.91 (s, 1H), 7.10 (s, 1H), 6.42 (s, 1H), 5.34 (s, 2H); MS LC-MS (M+H)+=178.2, RT=2.10 min.

1. filtrationThe precipitate was filtered off
2. concentrationthe filtrate was concentrated to ca. 20 mL
3. additionThe residue was diluted with water (100 mL)
4. additionneutralized by slow addition of sodium bicarbonate
5. extractionThe mixture was then extracted with methylene chloride (3×150 mL)
6. dry with materialdried over sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated to dryness

ORD record

ord-fabf8eebd7654d958661570f8bfa2d40

Source dataset

uspto-grants-2011_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08076488B2