4-Fluoronitrobenzene
4-Fluoronitrobenzene is an organic compound with the formula FC6H4NO2. It is one of three isomeric fluoronitrobenzenes. A yellow oil, it is prepared from 4-nitrochlorobenzene using the Halex process:
4-Fluoronitrobenzene can be hydrogenated to give 4-fluoroaniline, which is a precursor to the fungicide and parafluorofentanyl.
Owing to the presence of the electron withdrawing nitro group, the fluoride is a good leaving group in fluoronitrobenzenes. Thus reaction with phenoxide gives the mononitrodiphenylether.