Describe the methods of preparation of haloarenes.

(A) Aryl halides cannot be prepared by the methods used for alkyl halides because the $C-OH$ bond in phenols is much stronger than the $C-OH$ bond in alcohols.
$(a)$ Preparation from arenes by electrophilic substitution:
Method: Aryl chlorides and bromides are prepared by the reaction of arenes with chlorine $(Cl_2)$ or bromine $(Br_2)$ in the presence of a Lewis acid catalyst like iron or iron $(III)$ chloride.
Mechanism: This reaction proceeds via electrophilic aromatic substitution. The Lewis acid catalyst generates the electrophiles $Cl^+$ and $Br^+$.
Reactions: $C_6H_6 + X_2 \xrightarrow{Fe/FeX_3} C_6H_5X + HX$ (where $X = Cl, Br$).
The ortho and para isomers can be easily separated due to their large difference in melting points.
Iodination: The reaction is reversible,so an oxidizing agent like $HNO_3$ or $HIO_4$ is required to oxidize $HI$ formed during the reaction.
Fluorination: Fluorine is too reactive to be used directly for this method.
$(b)$ Preparation from amines by Sandmeyer reaction:
$(i)$ Diazotization: Primary aromatic amines dissolved or suspended in cold aqueous mineral acid are treated with sodium nitrite $(NaNO_2)$ to form diazonium salts $(ArN_2^+X^-)$.
$(ii)$ Sandmeyer reaction: The freshly prepared diazonium salt solution is treated with cuprous chloride $(Cu_2Cl_2)$ or cuprous bromide $(Cu_2Br_2)$ to replace the diazonium group with $-Cl$ or $-Br$.