What is the name of the following reaction?
`CH_3-CH_2-CH_2Br underset("Dry acetone")overset(NaI)(rarr) CH_3CH_2CH_2I`

Options

A. Sandmeyer reaction
B. Gattermann reaction
C. Finkelstein reaction
D. Swarts reaction

Answer

To determine the name of the reaction given by the equation:

\[ \text{CH}_3-\text{CH}_2-\text{CH}_2\text{Br} \xrightarrow{\text{Dry acetone}} \text{NaI} \rightarrow \text{CH}_3\text{CH}_2\text{CH}_2\text{I} \]

we can analyze the components and the process involved.

### Step-by-Step Solution:

1. **Identify the Reactants**:
- The reactant is propyl bromide (CH₃-CH₂-CH₂Br).
- The reagent used is sodium iodide (NaI) in dry acetone.

2. **Understanding the Reaction**:
- Sodium iodide (NaI) is a source of iodide ions (I⁻).
- In dry acetone, sodium iodide facilitates the substitution of bromine (Br) with iodine (I).

3. **Type of Reaction**:
- This reaction involves the substitution of one halogen (Br) with another halogen (I).
- The mechanism involved here is typically an \( S_N2 \) reaction, where the nucleophile (I⁻) attacks the carbon atom bonded to the leaving group (Br), resulting in the formation of propyl iodide (CH₃-CH₂-CH₂I).

4. **Name of the Reaction**:
- This specific reaction is known as the **Finkelstein reaction**. It is characterized by the exchange of halogens, particularly when sodium iodide is used to convert alkyl bromides or chlorides to alkyl iodides in the presence of a polar aprotic solvent like acetone.

### Final Answer:
The name of the reaction is the **Finkelstein reaction**.

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