Trifluoroacetic anhydride → 2-Bromo-4-fluorobenzonitrile
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
Product 1
Reagents, catalysts & solvents 1
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.