The major product formed in the reaction
`CH_(3)CH = CH - overset(O)overset(||)(C ) - CH_(3)underset(H_(2)O,CH_(3)OH)overset(NaBH_(4))rarr` is

Options

A. `CH_(3)CH = CHCH(OH)CH_(3)`
B. `CH_(3)CH_(2)CH(OH)CH_(3)`
C. `CH_(3)CH_(2)overset(OH)overset(|)(CH)COCH_(3)`
D. `CH_(3)CH_(2)CH_(2)COCH_(3)`

Explanation

To solve the problem, we need to analyze the reaction of the compound with sodium borohydride (NaBH4), which is a reducing agent. Here’s the step-by-step solution:

### Step 1: Identify the Reactant
The reactant given is:
\[ \text{CH}_3\text{CH}=\text{CH}-\overset{O}{\text{C}}-\text{CH}_3 \]
This structure consists of a double bond (alkene) and a ketone group (C=O).

### Step 2: Understand the Role of NaBH4
Sodium borohydride (NaBH4) is a selective reducing agent that primarily reduces carbonyl groups (like ketones and aldehydes) to alcohols. However, it does not affect carbon-carbon double bonds.

### Step 3: Determine the Reaction
In the given compound, the ketone group (C=O) will be reduced to an alcohol (C-OH) by NaBH4. The carbon-carbon double bond (C=C) will remain unchanged.

### Step 4: Write the Product
After the reduction of the ketone group, the product will be:
\[ \text{CH}_3\text{CH}=\text{CH}-\text{C(OH)}-\text{CH}_3 \]
This means that the ketone has been converted to an alcohol, while the alkene remains intact.

### Step 5: Finalize the Major Product
The major product formed from the reaction is:
\[ \text{CH}_3\text{CH}=\text{CH}-\text{C(OH)}-\text{CH}_3 \]

### Conclusion
The correct answer, which corresponds to the major product formed in this reaction, is option 1.

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