Can you explain the mechanism of the reaction (step-by-step) by which the alkene + HBr is changed into an alkyl halide?

Question

Christian Anderson · Accepted Answer

The mechanism involves two steps.

In Step 1, the π electrons in the double bond attack the HBr, producing an intermediate carbocation and leaving a negative bromide ion.

In Step 2, the bromide ion then joins to the positive carbon of the carbocation.

Carter Allen · Answer

undefined The reaction involves electrophilic addition. Here's the step-by-step mechanism:

1. **Initiation:** Homolytic cleavage of the Br-Br bond in HBr, forming two radicals.

2. **Propagation - Step 1:** One of the bromine radicals attacks the alkene, forming a bromine molecule and a primary alkyl radical.

3. **Propagation - Step 2:** The alkyl radical reacts with another HBr molecule, generating the alkyl bromide and regenerating the bromine radical.

4. **Termination:** Various reactions between radicals, leading to the formation of stable products.

This process results in the addition of HBr across the double bond, leading to the formation of an alkyl bromide.