Potassium Carbonate → 4-Fluoro-3-(pyridin-3-yl)aniline

HRID 586320Notes

Reaction equation

HRID 586320 reaction equation
Br[C:2]1[CH:3]=[C:4]([NH2:9])[CH:5]=[CH:6][C:7]=1[F:8].C(B(CC)[C:13]1[CH:14]=[N:15][CH:16]=[CH:17][CH:18]=1)C.C(=O)([O-])[O-].[K+].[K+]>COCCOC.O.C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[F:8][C:7]1[CH:6]=[CH:5][C:4]([NH2:9])=[CH:3][C:2]=1[C:13]1[CH:14]=[N:15][CH:16]=[CH:17][CH:18]=1

Participants

7

Conditions

Temperature
80 °C

Procedure

A mixture of 3-bromo-4-fluorophenylamine (7.92 g, 41.7 mmol), diethyl(3-pyridyl)borane (6.74 g, 45.9 mmol), tetrakis(triphenylphosphine)palladium(0) (0.96 g, 0.83 mmol) and potassium carbonate (17.26 g, 125 mmol) in 1,2-dimethoxyethane (30 ml) and water (15 ml) was heated at 80° C. for 20 h. After cooling to ambient temperature the reaction was partitioned between ethyl acetate (500 ml) and water (500 ml). The organics were washed with brine (400 ml), dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. Purification of the residue by flash chromatography (silica gel, 0-20% EtOAc/CH2Cl2) gave 4-fluoro-3-(pyridin-3-yl)phenylamine (3.64 g, 46%) as a colourless oil that solidified on standing to afford a white solid: 1H NMR (360 MHz, CDCl3) δ 3.65 (2H, s), 6.65-6.72 (2H, m), 6.99 (1H, dd, J 9, 9 Hz), 7.33-7.37 (1H, m), 7.84-7.86 (1H, m), 8.58 (1H, d, J 4 Hz), 8.76 (1H, m).

Workup

  1. temperatureAfter cooling to ambient temperature the reaction
  2. customwas partitioned between ethyl acetate (500 ml) and water (500 ml)
  3. washThe organics were washed with brine (400 ml)
  4. dry with materialdried over anhydrous sodium sulfate
  5. filtrationfiltered
  6. concentrationconcentrated in vacuo
  7. customPurification of the residue by flash chromatography (silica gel, 0-20% EtOAc/CH2Cl2)

Sources & evidence

ORD record
ord-466660e338dd478299cb5271e67e8627
Source dataset
uspto-grants-2005_08
Patent number
US06936608B2

Reaction notes

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