What product would be formed from the `S_(N)2` reaction of(S)-3-chlorohexane and hydroxide ion ?

Options

A. 2-butanol
B. (S) =-2-butanol
C. (R) -3-hexanol
D. 3-pentanol

Explanation

To determine the product formed from the \( S_N2 \) reaction of \( (S)-3 \)-chlorohexane and hydroxide ion, we can follow these steps:

### Step 1: Identify the Reactants
The reactants are \( (S)-3 \)-chlorohexane and hydroxide ion (\( OH^- \)). The structure of \( (S)-3 \)-chlorohexane has a chlorine atom as the leaving group.

### Step 2: Understand the \( S_N2 \) Mechanism
In an \( S_N2 \) reaction, the nucleophile attacks the electrophilic carbon atom from the opposite side of the leaving group, resulting in a complete inversion of configuration at that carbon. This is often referred to as "umbrella inversion."

### Step 3: Locate the Chiral Center
In \( (S)-3 \)-chlorohexane, the chiral center is at the third carbon, where the chlorine atom is attached. The configuration is \( S \) (sinister).

### Step 4: Perform the Nucleophilic Attack
The hydroxide ion (\( OH^- \)) will attack the carbon atom that is bonded to the chlorine atom. The chlorine atom will leave, and the hydroxide will take its place.

### Step 5: Determine the New Configuration
Since the \( S_N2 \) reaction involves inversion, the \( S \) configuration of \( (S)-3 \)-chlorohexane will become \( R \) after the nucleophilic substitution. Thus, the product will be \( (R)-3 \)-hexanol.

### Step 6: Write the Product Structure
The product of the reaction is \( (R)-3 \)-hexanol, which can be represented structurally as follows:
- The carbon chain remains the same, but the hydroxyl group (\( OH \)) replaces the chlorine atom at the third carbon.

### Conclusion
The product formed from the \( S_N2 \) reaction of \( (S)-3 \)-chlorohexane and hydroxide ion is \( (R)-3 \)-hexanol.

### Final Answer
The correct answer is option number 3: \( (R)-3 \)-hexanol.

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