What is the correct order of the relative yields of the following compounds when isopropylbenzene is reacted with Br ₂ in the presence of UV light? (i) (ii) (iii)

Step-by-step solution

The reaction of isopropylbenzene with Br ₂ in the presence of UV light proceeds via a free radical substitution mechanism at the alkyl side chain. The reaction involves the abstraction of a hydrogen atom by a bromine radical to form an alkyl radical intermediate. Bromination is highly selective and favors the formation of the most stable radical. Abstraction of the benzylic hydrogen yields a tertiary benzylic radical, which is highly stabilized by resonance with the benzene ring and hyperconjugation. This stable in