Question

Main Products formed during a reaction of 1-methoxy naphthalene with hydroiodic acid are :

• A. A
• B. B
• C. C
• D. D

Hint:

In $Ar-O-R$ ethers, the $Ar-O$ bond has partial double bond character. $HI$ will always cleave the $O-R$ bond, giving Phenol/Naphthol and Alkyl Iodide.

Answer 1

The Correct Option is D

Step 1: This is the cleavage of an ether (\(Ar-O-R\)) by \(HI\).
Step 2: In phenolic ethers, the bond between the Oxygen and the Aromatic ring (\(sp^2\) carbon) is very strong due to partial double bond character from resonance.
Step 3: The \(I^-\) ion attacks the smaller alkyl group (\(CH_3\)) via an \(S_N2\) mechanism, while the proton (\(H^+\)) attaches to the oxygen.
Step 4: Result: 1-Naphthol and Methyl Iodide (\(CH_3I\)).