Trifluoroacetic anhydride → 2-Bromo-4-fluorobenzonitrile

HRID 1284270Notes

Reaction equation

HRID 1284270 reaction equation
[Br:1][C:2]1[CH:10]=[C:9]([F:11])[CH:8]=[CH:7][C:3]=1[C:4]([NH2:6])=O.FC(F)(F)C(OC(=O)C(F)(F)F)=O>N1C=CC=CC=1>[Br:1][C:2]1[CH:10]=[C:9]([F:11])[CH:8]=[CH:7][C:3]=1[C:4]#[N:6]

Participants

4

Reactant 2

HCID 9845Trifluoroacetic anhydrideHCID 203722342-Bromo-4-fluorobenzamide

Product 1

HCID 1189392-Bromo-4-fluorobenzonitrile

Reagents, catalysts & solvents 1

HCID 1049PyridineSolvent

Procedure

A solution of 10.9 g. (0.05 mole) of 2-bromo-4-fluorobenzamide in 50 ml. of dry pyridine is stirred and cooled in an ice-bath while 11.2 g. (0.0525 mole) of trifluoroacetic anhydride is added dropwise. After 2 hours at room temperature, the bulk of the solvent is evaporated under reduced pressure and the residue is dissolved in ether. Evaporation of the washed and dried ethereal extract under reduced pressure leaves the product as the residual solid. Sublimation at 55°C. and 0.05 mm. yields white crystals, m.p. 75°-76.5°C. A sample from a previous experiment was resublimed for analysis, m.p. 77°-78°C.

Workup

  1. temperaturecooled in an ice-bath while 11.2 g
  2. customthe bulk of the solvent is evaporated under reduced pressure
  3. dissolutionthe residue is dissolved in ether
  4. customEvaporation of the
  5. washwashed
  6. customdried ethereal
  7. extractionextract under reduced pressure
  8. customleaves the product as the residual solid
  9. customat 55°C.
  10. customyields white crystals, m.p. 75°-76.5°C

Sources & evidence

ORD record
ord-4a7855118ec5449eab8f20a11467c798
Source dataset
uspto-grants-1976_08
Patent number
US03978127

Reaction notes

Loading…