` ( R )` -2-Iodobutane is treated with Nal in acetone and allowed to stand for a long time The product eventually fromed is .

Options

A. (R ) -2- lodobutane
B. S-2- lodobutane
C. `(+-) -2-` lodobutane
D. 2-Butane

Answer

To solve the question regarding the treatment of (R)-2-Iodobutane with sodium iodide (Nal) in acetone, we will analyze the reaction step by step.

### Step 1: Identify the Reactants
The reactant is (R)-2-Iodobutane. This compound is a chiral molecule, meaning it has a specific configuration (R) at the chiral center.

**Hint:** Remember that chiral centers have four different substituents attached to them, leading to optical activity.

### Step 2: Understand the Reaction Conditions
The reaction takes place in acetone, which is a polar aprotic solvent. Sodium iodide (Nal) is used, where iodide ion (I-) acts as a good nucleophile.

**Hint:** Polar aprotic solvents favor SN2 reactions because they do not solvate the nucleophile strongly, allowing it to be more reactive.

### Step 3: Mechanism of the Reaction
In an SN2 reaction, the nucleophile (I-) attacks the carbon atom bonded to the leaving group (iodine in this case). Since (R)-2-Iodobutane is chiral, the attack will lead to the inversion of configuration at the carbon center.

**Hint:** In SN2 reactions, the nucleophile attacks from the opposite side of the leaving group, resulting in inversion of stereochemistry.

### Step 4: Formation of Products
The attack by iodide ion (I-) on (R)-2-Iodobutane will lead to the formation of (S)-2-Butanol. However, because the reaction can occur repeatedly, there can be multiple attacks leading to both (R)- and (S)-2-Butanol being formed.

**Hint:** Consider that repeated SN2 reactions can lead to a mixture of products due to the possibility of multiple attacks.

### Step 5: Resulting Product Mixture
The final product will be a racemic mixture of (R)-2-Butanol and (S)-2-Butanol, which is represented as ±2-Butanol. A racemic mixture contains equal amounts of both enantiomers, making it optically inactive.

**Hint:** A racemic mixture is formed when both enantiomers are present in equal amounts, leading to no net optical activity.

### Conclusion
The product eventually formed from the reaction of (R)-2-Iodobutane with sodium iodide in acetone is **±2-Butanol**.

### Final Answer
The answer to the question is **±2-Butanol**.