Question

Question: Draw a stepwise mechanism for the following reaction.

Short answer

Mechanism for the formation of products

Step-by-step solution

Radical formation

The reagent ROOR undergoes homolytic fission to form two radical species.

Nature of HBr

HBr behaves opposite to its normal nature of attacking the carbon in the C=C with fewer hydrogen atoms. In the presence of radical species, the ion adds to the carbon with more hydrogen atoms.

Products of given reactions

ROOR undergoes homolytic fission to form its two radical fragments.

The radicals attack the HBr and thus form radicals. These radicals attack the diene to form two new radicals giving two products. The products and mechanism of the reaction are shown hereunder:

Now, the two radical structures react with HBr as: