In the reaction,
`H_3C-CH=CH-CH_2-CH_2-CN overset((i)AIH(t-Bu)_2 )underset((ii) H_2O)rarr`
Identify the product formed in the given reaction.

Options

A. `H_3C-CH_2CH_2CH_2CH_2CN`
B. `H_3C-CH=CH-CH_2CH_2CHO`
C. `H_3CCH_2CH_2CH_2CH_2CHO`
D. None of the above

Answer

To solve the problem, we need to analyze the given reaction step by step.

### Step 1: Identify the Reactants
The reactant given is:
\[ H_3C-CH=CH-CH_2-CH_2-CN \]
This molecule contains a double bond (C=C) and a cyano group (C≡N).

### Step 2: Identify the Reagent
The reagent used in the first step is:
\[ \text{AIH(t-Bu)}_2 \]
This is a type of aluminum hydride known as diisobutylaluminum hydride (DIBAL-H), which is a selective reducing agent.

### Step 3: Understand the Reaction Type
DIBAL-H is known for its ability to reduce nitriles (C≡N) to aldehydes (RCHO) without affecting double bonds. Therefore, in this reaction, the cyano group will be reduced to an aldehyde while the double bond will remain intact.

### Step 4: Perform the Reduction
When DIBAL-H reacts with the cyano group in the molecule, the following transformation occurs:
- The cyano group (C≡N) is reduced to an aldehyde (C=O).
- The double bond (C=C) remains unchanged.

The structure after this reduction will be:
\[ H_3C-CH=CH-CH_2-CH_2-CHO \]

### Step 5: Hydrolysis
The second step involves hydrolysis with water (H2O). However, since the double bond remains unchanged and the aldehyde is already formed, the hydrolysis does not further change the product.

### Final Product
The final product after the reaction is:
\[ H_3C-CH=CH-CH_2-CH_2-CHO \]
This is an aldehyde with the original double bond intact.

### Conclusion
The product formed in the given reaction is:
\[ H_3C-CH=CH-CH_2-CH_2-CHO \]

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