Ammonium Chloride → 2-Amino-4-bromo-5-(trifluoromethyl)phenol

To a mixture of zinc powder (16.23 g, 248 mmol) and ammonium chloride (13.28 g, 248 mmol) in MeOH (80 mL) was added 4-bromo-2-nitro-5-(trifluoromethyl)phenol (7.1 g, 24.8 mmol) and the reaction mixture was stirred overnight at ambient temperature. The reaction mixture was filtered and the filtrate was evaporated in vacuo. The residue was partitioned between EtOAc (100 mL) and water (300 mL). The organic phase was separated and washed with brine (30 mL), dried over Na2SO4, filtered and concentrated in vacuo to give 2-amino-4-bromo-5-(trifluoromethyl)phenol as a black oil (5.9 g, 93%), which was used in the next step without further purification. 1H NMR (DMSO-d6, 400 MHz): δ 9.89 (brs 1H), 6.98 (s, 1H), 6.92 (s, 1H), 5.53 (brs, 2H).

1. filtrationThe reaction mixture was filtered
2. customthe filtrate was evaporated in vacuo
3. customThe residue was partitioned between EtOAc (100 mL) and water (300 mL)
4. customThe organic phase was separated
5. washwashed with brine (30 mL)
6. dry with materialdried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated in vacuo

ORD record

ord-dfd6a09f69ad4fb88678eb372c78b069

Source dataset

uspto-grants-2015_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09115151B2