Question

Product [X] formed in the above reaction is:

• A.

  

• B. H₃C-CH₂-CH=CH₂
• C. H₃C-CH=CH-CH₃
• D.

  

Answer 1

The Correct Option is D

Step 1: Reaction with \( \text{NaI} \) and \( \text{H}_3\text{PO}_4 \)

The alcohol reacts with \( \text{NaI} \) and \( \text{H}_3\text{PO}_4 \) to form the corresponding iodoalkane via a nucleophilic substitution reaction. In this process:

• \( \text{H}_3\text{PO}_4 \) acts as an acid catalyst.
• \( \text{I}^- \) from \( \text{NaI} \) acts as the nucleophile, replacing the hydroxyl group with an iodine atom.

The reaction is as follows:

\[ \text{CH}_3-\text{CH}_2-\text{CH(OH)}-\text{CH}_3 \xrightarrow{\text{NaI, H}_3\text{PO}_4} \text{CH}_3-\text{CH}_2-\text{CH(I)}-\text{CH}_3 \]

Step 2: Formation of the Grignard Reagent

The iodoalkane reacts with magnesium in dry ether to form a Grignard reagent:

\[ \text{CH}_3-\text{CH}_2-\text{CH(I)}-\text{CH}_3 \xrightarrow{\text{Mg, Dry Ether}} \text{CH}_3-\text{CH}_2-\text{CH(MgI)}-\text{CH}_3 \]

Here:

• Dry ether is used as a solvent because it stabilizes the Grignard reagent and prevents it from reacting with water.

Step 3: Reaction with \( \text{D}_2\text{O} \)

The Grignard reagent reacts with deuterated water (\( \text{D}_2\text{O} \)) to form the deuterated alkane. The \( \text{C-MgI} \) bond is replaced by a \( \text{C-D} \) bond:

\[ \text{CH}_3-\text{CH}_2-\text{CH(MgI)}-\text{CH}_3 \xrightarrow{\text{D}_2\text{O}} \text{CH}_3-\text{CH}_2-\text{CH(D)}-\text{CH}_3 \]

Final Answer:

The product formed is \( \text{CH}_3-\text{CH}_2-\text{CH(D)}-\text{CH}_3 \).