Question

Match List - I with List - II. 

• A. (a)-(ii), (b)-(iii), (c)-(iv), (d)-(i)
• B. (a)-(iii), (b)-(ii), (c)-(i), (d)-(iv)
• C. (a)-(iv), (b)-(ii), (c)-(iii), (d)-(i)
• D. (a)-(ii), (b)-(iv), (c)-(iii), (d)-(i)

Hint:

It is crucial to know the specific outcomes of reactions with common reagents:
\textbf{Esters:} Hydrolysis \(\rightarrow\) Acid + Alcohol. Reduction with LiAlH\(_4\) \(\rightarrow\) Alcohols. Partial reduction with DIBAL-H \(\rightarrow\) Aldehyde.
\textbf{Nitriles:} Reaction with Grignard reagent/H\(_3\)O\(^+\) \(\rightarrow\) Ketone. Stephen Reduction (SnCl\(_2\)/HCl) \(\rightarrow\) Aldehyde. Complete reduction with LiAlH\(_4\) \(\rightarrow\) Primary Amine.
Creating a flowchart of these reactions can be very helpful for revision.

Answer 1

The Correct Option is A

Step 1: Understanding the Task
We need to match each chemical transformation in List-I with the correct reagent(s) from List-II that would accomplish it.
Step 2: Analyzing Each Transformation
(a) CH\(_3\)COOCH\(_2\)CH\(_3\) \(\rightarrow\) CH\(_3\)CH\(_2\)OH: This shows the conversion of ethyl acetate to ethanol. This occurs during the acid-catalyzed hydrolysis of the ester. The full reaction is CH\(_3\)COOCH\(_2\)CH\(_3\) + H\(_2\)O \(\xrightarrow{H^+}\) CH\(_3\)COOH + CH\(_3\)CH\(_2\)OH. The reagent H\(_2\)SO\(_4\)/H\(_2\)O (ii) facilitates this reaction.
Match: (a) \(\rightarrow\) (ii)
(b) CH\(_3\)COOCH\(_3\) \(\rightarrow\) CH\(_3\)CHO: This shows the partial reduction of an ester (methyl acetate) to an aldehyde (acetaldehyde). This specific transformation is achieved using Diisobutylaluminium hydride (DIBAL-H) at low temperatures, followed by hydrolysis. DIBAL-H is a selective reducing agent for this purpose.
Match: (b) \(\rightarrow\) (iii)
(c) CH\(_3\)C \(\equiv\) N \(\rightarrow\) CH\(_3\)CHO: This is the conversion of a nitrile (acetonitrile) to an aldehyde (acetaldehyde). This is a classic example of the Stephen reduction. The nitrile is first reduced by tin(II) chloride (SnCl\(_2\)) in the presence of hydrochloric acid (HCl) to an iminium salt, which upon hydrolysis (H\(_2\)O) yields the aldehyde.
Match: (c) \(\rightarrow\) (iv)
(d) CH\(_3\)C \(\equiv\) N \(\rightarrow\) CH\(_3\)COCH\(_3\): This reaction converts a nitrile to a ketone (acetone). This is achieved by reacting the nitrile with a Grignard reagent (CH\(_3\)MgBr). The nucleophilic methyl group from the Grignard reagent attacks the nitrile carbon, and subsequent hydrolysis of the intermediate imine yields the ketone.
Match: (d) \(\rightarrow\) (i)
Step 3: Compiling the Final Match
The correct matches are:
(a) - (ii)
(b) - (iii)
(c) - (iv)
(d) - (i)
This corresponds to option (A).