Reaction #1368

Reaction equation

potassium cyanide

ammonium hydroxide

2-methyl-3,4,6-trifluoroaniline

sulfuric acid

sodium nitrite

→

2-methyl-3,4,6-trifluorobenzonitrile

Yield 38.2%

Solvents

water

water

Conditions

Workup

1. 1
   Temperaturethe mixture is cooled
2. 2
   ExtractionThe mixture is extracted with dichloromethane
3. 3
   Dryingthe extract is dried over sodium sulfate
4. 4
   Concentrationconcentrated
5. 5
   Otherthe residue is purified with column chromatography (silica-gel, dichloromethane:n-hexane=1:4)

Procedure

To 2-methyl-3,4,6-trifluoroaniline (10.6 g) is added a mixture of conc. sulfuric acid (13.8 ml) and water (46 ml) and the mixture is cooled. Thereto an aqueous solution (20 ml) of sodium nitrite (5.5 g) is added dropwise at 0°-5° C. The solution is gradually added to a mixture of copper (II) sulfate 5 hydrate (41 g), potassium cyanide (43 g), ammonium hydroxide (60 ml) and water (260 ml) at 10°-30° C. The mixture is extracted with dichloromethane and the extract is dried over sodium sulfate, concentrated and the residue is purified with column chromatography (silica-gel, dichloromethane:n-hexane=1:4) to give 2-methyl-3,4,6-trifluorobenzonitrile (4.3 g).

Source