Acetophenone when reacted with a base `C_(2)H_(5)ONa` yields a stable compound which has the structure

Options

A.
B.
C.
D.

Explanation

To solve the question regarding the reaction of acetophenone with the base \( C_2H_5ONa \), we will follow these steps:

### Step 1: Identify the Reactants
Acetophenone is a ketone with the structure \( C_6H_5C(O)CH_3 \). The base given is sodium ethoxide (\( C_2H_5ONa \)), which will facilitate the reaction.

### Step 2: Understand the Reaction Mechanism
When acetophenone reacts with a base, it undergoes an aldol condensation reaction. This reaction involves the deprotonation of the alpha hydrogen of acetophenone, leading to the formation of an enolate ion.

### Step 3: Formation of Enolate Ion
The base \( C_2H_5ONa \) abstracts the alpha hydrogen from acetophenone, forming the enolate ion:
\[ C_6H_5C(O)CH_3 \xrightarrow{C_2H_5ONa} C_6H_5C(O)C^-H_2CH_3 \]

### Step 4: Nucleophilic Addition
The enolate ion then acts as a nucleophile and attacks the carbonyl carbon of another molecule of acetophenone:
\[ C_6H_5C(O)C^-H_2CH_3 + C_6H_5C(O)CH_3 \rightarrow \text{Beta-hydroxy ketone} \]

### Step 5: Formation of Beta-Hydroxy Ketone
This results in the formation of a beta-hydroxy ketone:
\[ \text{Beta-hydroxy ketone} \rightarrow C_6H_5C(OH)(C_6H_5)CH_2C(O)CH_3 \]

### Step 6: Elimination of Water
Upon heating, the beta-hydroxy ketone undergoes dehydration (loss of water) to form an alpha, beta-unsaturated ketone:
\[ C_6H_5C(OH)(C_6H_5)CH_2C(O)CH_3 \xrightarrow{\Delta} C_6H_5C=C(C_6H_5)C(O)CH_3 + H_2O \]

### Step 7: Final Structure
The final stable compound formed is an alpha, beta-unsaturated ketone, which has the structure:
\[ \text{Final structure: } C_6H_5C=C(C_6H_5)C(O)CH_3 \]

### Conclusion
The stable compound formed when acetophenone reacts with sodium ethoxide is an alpha, beta-unsaturated ketone.

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