Chemistry - Aromatic Hydrocarbon Question with Solution | TestHub
Which of the following will undergo sulphonation at fastest rate ?
Options:
Answer:
Solution:
Question Explanation:
The question asks to identify which alkyl-substituted benzene will undergo sulfonation at the fastest rate.
Concept:
This question is based on the activating effect of alkyl groups in Electrophilic Aromatic Substitution (EAS) reactions.
Solution:
Sulfonation, an EAS reaction, is accelerated by electron-donating groups like alkyls on the benzene ring. Alkyl groups are activating, ortho/para-directing due to their positive inductive effect () and hyperconjugation. The rate of EAS is proportional to the substituent's electron-donating power. The methyl group is the most electron-donating due to its positive inductive effect () and 3 alpha hydrogens for hyperconjugation.
Final Answer: Option (B)