Aryl chlorides and bromides can be easily prepared by electrophilic substitution of arenes with chlorine and bromine respectively in the presence of Lewis acid catalysts like iron or iron(III) chloride.

The ortho and para isomers can be easily separated due to large difference in their melting points. Reactions with iodine are reversible in nature and require the presence of an oxidising agent (HNO3, HIO4) to oxidise the HI formed during iodination. Fluoro compounds are not prepared by this method due to high reactivity of fluorine.

What is the product formed when Nitrobenzene reacts with fluorine in the presence of FeF₃ at 1400C?

No reaction

Aryl fluorides cannot be prepared as fluorine is too reactive in electrophilic substitution reactions.