Identify the final major product for the following reaction ?
Anline `underset(O-5^(@)C)overset(NaNO_(2)+HCl)rarr P overset(beta-"napthol")rarr Q`

Options

A.
B.
C.
D.

Explanation

To solve the question regarding the final major product of the given reaction, we will follow the steps outlined in the video transcript.

### Step-by-Step Solution:

1. **Identify the Starting Material:**
The starting material is aniline, which has the structure:
\[ \text{C}_6\text{H}_5\text{NH}_2 \]

2. **Reaction with Sodium Nitrite and Hydrochloric Acid:**
When aniline reacts with sodium nitrite (NaNO₂) in the presence of hydrochloric acid (HCl) at a low temperature (0-5°C), it undergoes diazotization to form benzene diazonium chloride (P). The reaction can be represented as:
\[ \text{C}_6\text{H}_5\text{NH}_2 + \text{NaNO}_2 + \text{HCl} \rightarrow \text{C}_6\text{H}_5\text{N}_2^+\text{Cl}^- + \text{H}_2\text{O} \]
Here, the product P is benzene diazonium chloride.

3. **Reaction with Beta-Naphthol:**
The next step involves the reaction of the benzene diazonium chloride (P) with beta-naphthol. Beta-naphthol has the structure:
\[ \text{C}_{10}\text{H}_7\text{OH} \]
When benzene diazonium chloride reacts with beta-naphthol, it leads to the formation of a colored azo dye (Q). The reaction can be represented as:
\[ \text{C}_6\text{H}_5\text{N}_2^+\text{Cl}^- + \text{C}_{10}\text{H}_7\text{OH} \rightarrow \text{C}_6\text{H}_5\text{N}_2\text{C}_{10}\text{H}_6\text{OH} \]
This product is an azo compound where the diazonium group is attached to the beta-naphthol.

4. **Final Product (Q):**
The final product (Q) is the azo dye formed from the reaction of benzene diazonium chloride with beta-naphthol. The structure of Q can be depicted as:
\[ \text{C}_6\text{H}_5\text{N}_2\text{C}_{10}\text{H}_6\text{OH} \]
This compound is characterized by the presence of the azo group (-N=N-) linking the phenyl ring from aniline and the naphthol.

### Conclusion:
The final major product (Q) of the reaction sequence is the azo dye formed from the reaction of benzene diazonium chloride with beta-naphthol.

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