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1,3,5-trihydroxybenzene (phloroglucinol) is treated with excess CH3I in the presence of KOH. Which of the following statements about this reaction and its major product are correct? (A) The formation of the major product involves nucleophilic substitution. (B) The reaction involves an acid-base step. (C) The major product contains six methyl groups. (D) The major product is a triketo compound.

1. The formation of major product involves nucleophilic substitution
2. It involves acid-base reaction
3. The major product has six methyl groups
4. The major product is triketo compound

Correct answer: The formation of major product involves nucleophilic substitution

Solution

KOH first deprotonates the OH groups (acid-base) and the resulting phenoxide nucleophile attacks CH3I (nucleophilic substitution — Williamson synthesis). The major product is 1,3,5-trimethoxybenzene with only 3 methyl groups. Both A and B are correct, but among the listed single options A best captures the reaction mechanism identity.

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