`Poverset(PCl_(5),0^(@)C)(rarr)Qunderset(-2HCl (ii)H^(+))overset((i)NaNH_(2)("excess"))(rarr)Roverset(NaNH_(2))(rarr)Soverset(I-CH_(3))(rarr)T-` P is

Options

A.
B.
C.
D.

Answer

To solve the question, we need to identify the compound P based on the series of reactions described. Let's break down the steps involved in the reactions and determine what P could be.

### Step-by-Step Solution:

1. **Identify the Reaction with PCl5:**
- When P is treated with PCl5 at 0°C, it forms Q. PCl5 is known to convert carbonyl compounds into corresponding chlorinated products.
- The product Q is likely a xaminal dichloride, which suggests that P could be a carbonyl compound (like an aldehyde or ketone).

2. **Formation of Q:**
- The reaction of a carbonyl compound with PCl5 typically results in the formation of a compound with two chlorine atoms attached to the carbon that was originally part of the carbonyl group.
- For example, if P is acetone (CH3COCH3), the reaction with PCl5 would yield a dichloride.

3. **Reaction of Q with NaNH2:**
- When Q is treated with excess sodium amide (NaNH2), it removes two HCl molecules. This indicates that Q must have at least two chlorine atoms and enough hydrogen atoms to allow for the formation of an alkyne.
- The product after this reaction would be an alkyne (let’s denote it as R).

4. **Formation of R:**
- The alkyne R is formed by the elimination of HCl from Q. This means that Q must have had two chlorines and at least two hydrogen atoms adjacent to the carbon atoms involved in the triple bond formation.

5. **Reaction of R with NaNH2 Again:**
- R is then treated with NaNH2 again, which suggests that R has acidic hydrogens that can be removed to form a sodium salt (denote this as S).

6. **Formation of S:**
- The sodium salt S is formed from R by the removal of acidic hydrogen atoms.

7. **Final Reaction with Methyl Iodide (I-CH3):**
- Finally, S is treated with methyl iodide (CH3I), which leads to the substitution of the sodium ion with a methyl group, resulting in the final product T.

8. **Identifying P:**
- After analyzing the reactions, we can conclude that P must be a carbonyl compound that can undergo these transformations. The most suitable candidate based on the reactions is likely to be a ketone or aldehyde that can yield the required products through these steps.

### Conclusion:
After evaluating the options and the reactions, we find that the most plausible structure for P is a carbonyl compound that can lead to the formation of a xaminal dichloride, followed by the necessary transformations to yield the final product T.