Consider the following sequence of reaction and identify the final product (Z).
`CH_(3)CH_(2)CH_(2)Br overset("Mg dry ether")rarr (X) overset(CO_(2))rarr (Y) overset(H^(+))rarr(Z)`

Options

A. `CH_(3)CH_(2)COOH`
B. `CH_(3)CH_(2)CH_(2)CH_(2)COOH`
C. `CH_(3)-underset(CH_(3))underset("| ")"CH"-COOH`
D. `CH_(3)CH_(2)CH_(2)COOH`

Answer

To solve the problem step by step, let’s analyze the sequence of reactions provided:

1. **Starting Material**: The starting compound is 1-bromopropane (CH₃CH₂CH₂Br).

2. **Formation of Grignard Reagent (X)**:
- When 1-bromopropane reacts with magnesium (Mg) in dry ether, it forms a Grignard reagent.
- The reaction can be represented as:
\[ \text{CH}_3\text{CH}_2\text{CH}_2\text{Br} + \text{Mg} \xrightarrow{\text{dry ether}} \text{CH}_3\text{CH}_2\text{CH}_2\text{MgBr} \quad (X) \]
- Here, (X) is the Grignard reagent, which is propylmagnesium bromide (CH₃CH₂CH₂MgBr).

3. **Reaction with Carbon Dioxide (Y)**:
- The Grignard reagent (X) is then treated with carbon dioxide (CO₂).
- The reaction can be represented as:
\[ \text{CH}_3\text{CH}_2\text{CH}_2\text{MgBr} + \text{CO}_2 \rightarrow \text{CH}_3\text{CH}_2\text{CH}_2\text{COO}^- + \text{MgBr}^+ \]
- This results in the formation of a carboxylate ion (Y), which is propanoate ion (CH₃CH₂CH₂COO⁻).

4. **Protonation to form Final Product (Z)**:
- The carboxylate ion (Y) is then treated with a proton source (H⁺), typically an acid.
- The reaction can be represented as:
\[ \text{CH}_3\text{CH}_2\text{CH}_2\text{COO}^- + \text{H}^+ \rightarrow \text{CH}_3\text{CH}_2\text{CH}_2\text{COOH} \quad (Z) \]
- This results in the formation of butanoic acid (CH₃CH₂CH₂COOH).

Thus, the final product (Z) is butanoic acid.

### Final Answer:
The final product (Z) is butanoic acid (CH₃CH₂CH₂COOH).

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