When HBr adds on hex-1-ene in the presence of benzoyl peroxide, the product is

Options

A. 2-bromohexane
B. 2, 3-dibromohexane
C. 1,2-dibromohexane
D. 1-bromohexane

Explanation

To solve the problem of what product is formed when HBr adds to hex-1-ene in the presence of benzoyl peroxide, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Reaction Conditions**:
- We are given hex-1-ene, which has the structure CH2=CH-CH2-CH2-CH2-CH3.
- The presence of benzoyl peroxide indicates that the reaction will proceed via a free radical mechanism rather than the typical electrophilic addition.

2. **Formation of Free Radicals**:
- Benzoyl peroxide decomposes upon heating or in the presence of light to form benzoyloxy radicals (PhO•).
- The benzoyloxy radical can then abstract a hydrogen atom from HBr, generating a bromine radical (Br•) and a phenyl radical.

3. **Radical Addition to the Alkene**:
- The bromine radical (Br•) will add to the double bond of hex-1-ene.
- The addition can occur at either the first carbon (C1) or the second carbon (C2) of the double bond.

4. **Determining the Most Stable Radical**:
- If Br• adds to C1, the resulting radical will be a primary radical (less stable).
- If Br• adds to C2, the resulting radical will be a secondary radical (more stable).
- Secondary radicals are more stable due to hyperconjugation and the inductive effect from adjacent carbon atoms.

5. **Final Product Formation**:
- Therefore, the bromine radical will preferentially add to C2, resulting in the formation of a secondary radical.
- The final product after the addition of HBr will be 1-bromohexane (C1) and the radical will be on C2.

### Final Answer:
The product formed when HBr adds to hex-1-ene in the presence of benzoyl peroxide is **1-bromohexane**.

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