Question

Draw the structures of major monohalo products in each of the following reactions:

\( \text{CH}_3\text{C}_6\text{H}_5 + \text{HI} \longrightarrow \) ?
(b) \( \text{C}_6\text{H}_6 + \text{Br}_2 \longrightarrow \) Heat or UV light ?

Hint:

In electrophilic aromatic substitution reactions, such as halogenation, the halogen adds to the aromatic ring in the presence of a catalyst or UV light.

Answer 1

(a) The reaction of methylbenzene (\(\text{CH}_3\text{C}_6\text{H}_5\)) with hydrogen iodide (HI) will lead to the formation of \(\text{C}_6\text{H}_5\text{CH}_3\) (toluene) as the product, with the substitution of a halogen atom at the benzene ring.
(b) The reaction of benzene (\(\text{C}_6\text{H}_6\)) with bromine (\(\text{Br}_2\)) in the presence of heat or UV light undergoes a radical substitution reaction to form bromobenzene (\(\text{C}_6\text{H}_5\text{Br}\)).