2,4-Difluoro-5-nitrophenol → 5-Amino-2,4-difluorophenol

HRID 2165177Notes

Reaction equation

HRID 2165177 reaction equation
[F:1][C:2]1[CH:7]=[C:6]([F:8])[C:5]([N+:9]([O-])=O)=[CH:4][C:3]=1[OH:12].[H][H]>CO.[Ni]>[F:1][C:2]1[CH:7]=[C:6]([F:8])[C:5]([NH2:9])=[CH:4][C:3]=1[OH:12]

Participants

5

Reactant 2

HCID 109210242,4-Difluoro-5-nitrophenolHCID 178418361HCID 178418361, compound2×

Product 1

HCID 27829995-Amino-2,4-difluorophenolYield 90.5%

Reagents, catalysts & solvents 2

HCID 935NickelCatalystHCID 887MethanolSolvent

Procedure

24 g of 2,4-Difluoro-5-nitrophenol, dissolved in 120 ml of methanol, are subjected to hydrogenation at a hydrogen pressure of 20-40 bar at 25°-45° C. in the presence of 2 g of Raney nickel. When constant pressure is reached (i.e. when the take-up of hydrogen is complete), the pressure is released and the mixture is cooled, the solution is free from catalyst by filtration, and the methanol is subsequently removed by distillation at reduced pressure. 18 g (GC purity 97.5%) of 2,4-difluoro-5-amino-phenol are obtained.

Workup

  1. temperaturethe mixture is cooled
  2. filtrationthe solution is free from catalyst by filtration
  3. customthe methanol is subsequently removed by distillation at reduced pressure

Sources & evidence

ORD record
ord-6657fbf79d384c8b8db03f38598113b8
Source dataset
uspto-grants-1990_07
Patent number
US04939170

Reaction notes

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