Dimethylformamide → 4-Amino-2,3-difluorobenzonitrile

HRID 1607189Notes

Reaction equation

HRID 1607189 reaction equation
Br[C:2]1[CH:8]=[CH:7][C:5]([NH2:6])=[C:4]([F:9])[C:3]=1[F:10].[CH3:11][N:12](C=O)C.[C-]#N.[Na+]>O>[NH2:6][C:5]1[CH:7]=[CH:8][C:2]([C:11]#[N:12])=[C:3]([F:10])[C:4]=1[F:9]

Participants

5

Reactant 3

HCID 6228DimethylformamideHCID 8929Sodium CyanideHCID 146210374-Bromo-2,3-difluoroaniline

Product 1

HCID 146210384-Amino-2,3-difluorobenzonitrileYield 55%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

A stirred mixture of the crude 4-bromo-2,3-difluoroaniline, 36 g of cuprous cyanide and 908 mL of DMF is heated 7 hours at reflux under an N2 atmosphere. After cooling, 900 mL of 10% aqueous NaCN is added and 45 minutes later 2 L of H2O. The black solution is extracted three times with CH2Cl2 (total volume 4 L). The CH2CL2 extract is washed with H2O, saturated NaHCO3 and H2O (500 mL of each) and then stripped in vacuo. The resulting black oil is purified by dry-column chromatography on silica gel using CH2CL2 as eluent. There is obtained 31.17 g (55% overall yield) of 4-amino-2,3-difluorobenzonitrile, m.p. 108°-110° C., with the expected ion at 156 in the mass spectrum and consistent NMR and IR spectral data.

Workup

  1. temperatureis heated 7 hours
  2. temperatureat reflux under an N2 atmosphere
  3. temperatureAfter cooling
  4. extractionThe black solution is extracted three times with CH2Cl2 (total volume 4 L)
  5. extractionThe CH2CL2 extract
  6. washis washed with H2O, saturated NaHCO3 and H2O (500 mL of each) and
  7. customThe resulting black oil is purified by dry-column chromatography on silica gel using CH2CL2 as eluent

Sources & evidence

ORD record
ord-77066bbe31194802b84ae626da93ef86
Source dataset
uspto-grants-1989_09
Patent number
US04863959

Reaction notes

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