When propene reacts with HBr in the presence of organic peroxides, the major product is:
Apropan-$1$-ol
Bpropane
C$2$-bromopropane
D$1$-bromopropane
Answer & Solution
Correct answer: D. $1$-bromopropane
Peroxides switch the mechanism from ionic to free-radical (peroxide / Kharasch effect). The radical adds anti-Markovnikov, so Br lands on the *less* substituted carbon — giving 1-bromopropane.
The trap is option B (Markovnikov product) — that's the answer without peroxides. The peroxide effect is specific to HBr; HCl and HI do not show it.
Related questions
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