What is the product 'Z' in the following reaction sequence?
Show Hint
Pay close attention to reaction conditions in aromatic substitution. For toluene:
- Halogenation with Fe/dark (electrophilic substitution) occurs on the ring at ortho/para positions.
- Halogenation with UV light/heat (free-radical substitution) occurs on the methyl group side-chain, forming benzyl halide.
Step 1: X Formation (Sandmeyer Reaction):
Benzene Diazonium Chloride reacts with \( \text{Cu}_2\text{Cl}_2/\text{HCl} \) to form Chlorobenzene (X).
Step 2: Y Formation (Wurtz-Fittig Reaction):
Chlorobenzene reacts with Methyl Chloride (\( \text{CH}_3\text{Cl} \)) and Sodium in dry ether.
\( \text{Ph-Cl} + 2\text{Na} + \text{CH}_3\text{-Cl} \to \text{Ph-CH}_3 + 2\text{NaCl} \).
Product Y is Toluene.
Step 3: Z Formation (Electrophilic Substitution):
Toluene reacts with \( \text{Cl}_2 \) in the presence of \( \text{Fe} \) (Lewis acid catalyst) in the dark.
The \( -\text{CH}_3 \) group is activating and ortho-para directing.
Electrophilic chlorination occurs on the benzene ring.
The products are o-Chlorotoluene and p-Chlorotoluene.
The para-isomer is usually the major product due to less steric hindrance.
Product Z is p-Chlorotoluene.
Was this answer helpful?
0
Top Questions on Organic Compounds Containing Nitrogen
