`Ph-underset(14)overset(O)overset("||")(C)-CHN_(2) underset(H_(2)O)overset(Ag_(2)O)(rarr)(A)`, product (A) is :

Options

A. `Ph–^(14)CH_(2) – CO_(2)H`
B. `Ph– CH_(2) –^(14)CO_(2)H`
C. `Ph–^(14)CO_(2)H`
D. `Ph– CO_(2)H`

Answer

To solve the question regarding the reaction of a compound with the formula Ph-CO-CH2-N2 in the presence of Ag2O and H2O, we will follow the steps of the reaction mechanism.

### Step-by-Step Solution:

1. **Identify the Reactant**:
The reactant is Ph-CO-CH2-N2, where Ph represents the phenyl group (C6H5), CO is a carbonyl group (C=O), and CH2 is a methylene group attached to a nitrogen (N2) group.

2. **Reaction with Silver Oxide (Ag2O)**:
When this compound is treated with silver oxide (Ag2O) and water (H2O), the nitrogen gas (N2) is released. The release of N2 is a driving force for the reaction, making it favorable.

3. **Formation of Carbene**:
The reaction leads to the formation of a carbene intermediate. The structure can be visualized as:
- Ph-CO-CH2 (with a carbene at the CH2 position).
The nitrogen gas (N2) leaves, and we are left with a carbene.

4. **Migration of the Phenyl Group**:
The next step involves the migration of the phenyl group to the carbene. The lone pair from the oxygen in Ag2O facilitates this migration. This results in the formation of a new compound:
- Ph-CH=C=O (with the phenyl group now attached to the carbene).

5. **Hydration Reaction**:
Water (H2O) then attacks the carbonyl carbon. The oxygen from water donates a lone pair to form a bond with the carbon, leading to the formation of a tetrahedral intermediate:
- The structure now has a hydroxyl group (OH) and a positive charge on the oxygen.

6. **Rearrangement and Final Product**:
The oxygen will then rearrange, and the double bond will shift back to the carbon, resulting in the final product:
- Ph-CH2-COOH (where the carbonyl has been converted to a carboxylic acid).

7. **Identifying the Product**:
The final product (A) is Ph-CH2-COOH, which corresponds to the second option provided in the question.

### Final Answer:
The product (A) is Ph-CH2-COOH.

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