Question

The major product ‘P’ for the following sequence of reactions is :

• A.
• B.
• C.
• D.

Hint:

When solving reaction sequences:
   Analyze each reagent step-by-step and apply known reaction mechanisms.
   Clemmensen reduction (Zn/Hg, HCl) is used to reduce carbonyl groups to methylene (\(-\text{CH}_2-\)).
   LiAlH\(_4\) reduces amides to amines.

Answer 1

The Correct Option is D

 To determine the major product 'P' of the given reaction sequence, we need to analyze the steps involved in the chemical transformation.

1. The first step is the Clemmensen reduction, which uses zinc amalgam (Zn/Hg) and hydrochloric acid (HCl) to convert the carbonyl group (C=O) into a methylene group (-CH₂-). This step is particularly effective in reducing ketones to alkanes.
2. In the second step, lithium aluminium hydride (LiAlH₄) is used. It is a powerful reducing agent that typically reduces aldehydes, ketones, carboxylic acids, and esters to alcohols. However, in this context, it will reduce the imide or amide group to an amine.
3. The third step involves acidic workup, which protonates any non-neutralized functional groups and ensures that the reaction goes to completion.

After understanding each step, we can conclude that the major product 'P' is the one where:

• The ketone group is reduced to an alkane in the first step.
• The amide group is further reduced to an amine in the second step.

 

Thus, 'P' is effectively a fully reduced form of the starting material, incorporating these changes. The correct structure will match the final reduced product.

The structure shown in the image above (Product 4) is the correct major product 'P' following the given reaction sequence. The other options do not incorporate both the reduction of the carbonyl and the amide group effectively.